Minerals in the Economy of Alabama, 2007 - Geological Survey of ...

Cover photograph:View of large-scale crushed stone (limestone/dolomite) operation in eastern Tuscaloosa County,Alabama (courtesy Vulcan Materials Company). Crushed stone accounts for about 28 percent ofthe total value of mineral production in Alabama.

GEOLOGICAL SURVEY OF ALABAMABerry H. (Nick) Tew, Jr.State GeologistGEOLOGIC INVESTIGATIONS PROGRAMMINERALS IN THE ECONOMY OF ALABAMA, 2007Information Series 64RbyLewis S. DeanTuscaloosa, Alabama2008

GEOLOGICAL SURVEY OF ALABAMABerry H. (Nick) Tew, Jr.State Geologist420 Hackberry LaneP.O. Box 869999Tuscaloosa, Alabama 35486-6999Phone (205)349-2852Fax (205)349-2861www.gsa.state.al.usAugust 20, 2008The Honorable Bob RileyGovernor of AlabamaMontgomery, AlabamaDear Governor Riley:It is with pleasure that I make available to you this report entitled Minerals in theEconomy of Alabama, 2007, by Lewis S. Dean, which has been published as InformationSeries 64R by the Geological Survey of Alabama.Mineral resources are the basis of an important part of Alabama's industrial economy. In2007 Alabama ranked sixteenth among the states in value of nonfuel minerals produced. Theestimated value of industrial mineral production in Alabama for 2007 was $1.34 billion,about 2 percent of the value of the total national mineral production. The Geological Surveyof Alabama has legislative mandate to evaluate the state's mineral resources and thereforecarries out a comprehensive minerals assessment program for the state. Under this program,many reports and maps are published annually, providing citizens and potential mineralindustry with basic information useful for the development of these resources.This summary report provides a brief overview of Alabama's minerals and relatedindustry for 2007.Respectfully,Berry H. (Nick) Tew, Jr.State GeologistScience and Service for the People of Alabama

CONTENTS—continuedPageZeolite minerals................................................................................................................ 21Further reading ...................................................................................................................... 21References cited .................................................................................................................... 22ILLUSTRATIONSFigure 1. Value of industrial and construction mineral production in Alabama, 1980-2007 ........................................................................................................................ 22. Map of Alabama showing physiographic provinces and counties ........................... 43. Example of a quadrangle series geologic map available for selected areasfrom the Geological Survey of Alabama.................................................................. 54. Varicolored clays and shales along the contact of the Coastal Plain andAppalachian Plateaus, south of Hamilton, Marion County, Alabama ...................... 85. Generalized distribution of limestone, dolomite, and marble resources inAlabama .................................................................................................................. 116. Quarry operation at Glenco, Etowah County, Alabama, for crushed limestone ...... 137. General distribution of sand and gravel resources in Alabama............................... 158. Quartz gravel aggregate.......................................................................................... 16TABLESTable 1. Production and number of employees in mining of coal and industrial mineralresources in Alabama for fiscal years 2005-2007 ................................................... 32. Production of limestone/dolomite by county in Alabama, 2000-2007...................... 63. Production of sand and gravel by county in Alabama, 2000-2007 .......................... 74. Production of selected clays in Alabama, 2000-2007 ............................................. 9

4Figure 2.—Map of Alabama showing physiographic provinces and counties.

5Figure 3.—Example of a quadrangle series geologic map available forselected areas from the Geological Survey of Alabama.commodity or a mineral deposit. For example,some types of minerals and natural resourceswithin the regional influence of theTennessee-Tombigbee Waterway mayincrease in value because of availability oflower cost transportation.Use of current and historical nonfuelmineral production data can provide insightinto mineral exploration, consumption, andtrade for assessing the economic andtechnical development of the state's mineralindustries. The earliest commercial operation

6was in 1780 for clay used in making brick,tile, and pottery at Mobile. Other earlycommercial production occurred in 1809 inWashington County for salt, 1818 in FranklinCounty for iron ore, 1827 in TuscaloosaCounty for sandstone (building stone), 1831in Chilton County for gold, 1838 in TalladegaCounty for marble, and 1840 for lime andlimestone. Mineral production was firstrecorded in Alabama in 1840 for clay (brickand earthenware), stone (limestone andmarble), iron, and gold. Since the 1840s,limestone and dolomite (and associatedmanufacture of lime), sand and gravel, ironore (up to 1975), clay, marble, bauxite, andsandstone were the principal mineralsproduced in Alabama (Dean, 2000).From 2000-2007, more limestone anddolomite were produced than any otherminerals in Alabama. The major productionareas are as follows: Shelby County (40percent) and Jefferson County (15 percent)from the Cambrian Conasauga Formationand Ketona Dolomite and the OrdovicianNewala Limestone; and Madison County (6percent), Colbert County (9 percent), andMorgan County (6 percent) from theMississippian Bangor and TuscumbiaLimestones (table 2).Sand and gravel production from 2000-2007 has come primarily from Quaternaryalluvium and terrace deposits in MontgomeryCounty (14 percent), Mobile County (10percent), Elmore County (8 percent), MaconCounty (5 percent), Tuscaloosa County (2percent), and Russell County (5 percent), andfrom the Citronelle Formation in MobileCounty (7 percent) (table 3). Clay productionhas consisted of brick and common clay (58percent), fuller's earth (20 percent), shale (12percent), kaolin (4 percent), bentonite (3percent), and bauxite (3 percent).Currently, other significant productionconsists of lime, cement, salt, building stone,synthetic gypsum, gemstones, iron oxidepigments, and recovered sulfur (U.S.Geological Survey, 2007a). These productiontrends are expected to continue in 2008. Thefollowing information provides details of theoccurrence, mining history, and generaleconomics of specific mineral resources inAlabama.BAUXITEBauxite is a mixture of hydrated aluminumoxide minerals (principally gibbsite) andmineral impurities formed by the weatheringof aluminum-bearing rocks. Bauxite was firstmined in Alabama in 1891 from Rock Run inCherokee County. In the 1940s, ore fromCalhoun, Cherokee, St. Clair, and ColbertCounties was mined and shipped to ReynoldsMetals Company at Muscle Shoals forexperimental production of aluminum. Miningceased when sufficient tonnage ofmetallurgical-grade bauxite became difficultto obtain.Table 2.--Production (short tons) of limestone/dolomite by county in Alabama, 2000-2007Data Sources: Modified from Alabama Department of Industrial Relations,Office Mine of Safety and Inspection (2000-2007).Year Shelby* Jefferson* Madison Colbert Morgan Other*2007 21,979,261 7,023,167 1,183,647 5,074,319 2,905,582 15,245,2942006 20,486,051 6,905,091 3,992,785 5,123,983 2,229,948 17,212,9062005 19,377,987 7,289,966 3,522,679 4,915,032 2,234,856 13,828,0442004 19,695,015 7,658,607 3,546,982 4,787,994 2,258,550 13,698,5552003 19,866,357 7,632,369 2,766,845 4,138,349 2,109,151 12,194,9752002 21,378,773 7,390,626 3,020,816 3,153,257 1,888,056 10,474,2472001 15,792,431 6,816,500 3,329,155 3,724,577 1,533,222 10,440,6872000 14,840,589 7,136,408 2,416,303 3,148,602 2,180,702 8,390,506*Includes dolomite.

7Table 3.--Production (short tons) of sand and gravel by county in Alabama, 2000-2007Data Sources: Alabama Department of Industrial Relations,Office of Mine Safety and Inspection (2000-2007).Year Montgomery Mobile Elmore Macon Tuscaloosa Russell Other2007 2,801,508 3,003,018 1,635,418 1,759,317 399,532 1,032,752 13,541,7502006 3,362,795 3,798,101 1,082,178 1,887,648 261,692 1,236,427 12,289,4632005 2,663,316 979,200 1,087,381 339,216 209,144 930,013 10,009,2372004 3,038,461 1,253,086 1,014,854 302,184 214,052 360,000 8,227,2192003 2,551,345 1,266,537 1,084,240 109,351 198,371 240,000 7,870,5412002 2,202,033 1,474,034 1,500,223 220,000 243,456 935,000 6,519,2882001 406,530 506,000 1,261,148 400,000 261,083 1,000,000 4,453,1822000 653,314 294,696 1,107,166 543,495 235,000 900,000 5,273,506The major economic bauxite deposits inAlabama occur in the Barbour-HenryCounties (Eufaula) bauxite district withinkaolinitic clay deposits, which are overlain bysands and clays of the Nanafalia Formation.Production began in 1927 and has beenmaintained on a continuous basis. Becauseof the irregular distribution of the bauxitedeposits, considerable exploratory test drillingmust be done prior to mining (Clarke, 1973).Alabama bauxite from the Eufaula district isused in making high-temperature refractoryproducts, abrasives, and chemicals.BUILDING STONEMany stone materials in the state,including sandstone, limestone, granite,quartzite, and marble, have been used forbuilding construction or ornamental stone.Annual production in Alabama for dimensionstone is about 4,430 metric tons valued atabout $3.63 million (U.S. Geological Survey,2007b).Naturally dimensioned blocks and flags ofsandstone and limestone have been widelyused in north Alabama. A unique tan- to buffcoloredsandstone (Pottsville Formation)characterized by small-scale sedimentarystructures is produced from Blount andCherokee Counties for use as exteriorbuilding stone, walkways, and patios(Fousek, 2002). Limestone (BangorLimestone) quarried at Rockwood in FranklinCounty also has been widely used. Whitemarble quarried at Sylacauga has been usedthroughout the United States for monumentsand for exterior and interior building stone(see Marble). A recently developed buildingstone operation in Lauderdale County wasthe first operation in Alabama to marketvaricolored "marble" (polished limestone) ofSilurian age. In south Alabama, softlimestone of the Clayton Formation, MariannaLimestone, and Salt Mountain Limestone wassaw-quarried in the 1800s and early 1900sfor building stone.CEMENTThe cement-manufacturing industry is amajor consumer of raw materials in the state.This industry began in Alabama in 1895 andhas since played a key role in thedevelopment of the state. Primary uses arefor ready-mix concrete, concrete products,building materials, and highway construction.The principal raw materials used in makingcement are limestone or chalk, clay andshale, silica, and iron oxide. Annual cementproduction in Alabama has increased to 5.1million metric tons of portland cement and475,000 metric tons of masonry cement.Annual production value of cement inAlabama is about $475.8 million (U.S.Geological Survey, 2007a).CHERTChert is a siliceous stone oftenassociated with weathered limestone or

8dolomite. It is a low value mineral commodity,but where a need exists for fill or basematerial for roads, chert deposits are ofeconomic value. Chert quarries have beendeveloped in most counties in north Alabamawhere the Fort Payne Chert and Knox Groupresiduum occur.CLAY AND SHALEClay and shale of variable compositionand character occur throughout the state (fig.4). Bentonite, kaolin, fuller's earth, fireclay,common clays, and shale are mined in thestate and used for making brick, tile,refractory and ceramic products, clay pipe,pottery, and lightweight aggregate (table 4).Brick plants are located in Bessemer, PhenixCity, Montgomery, Leeds, Ragland,Huntsville, Selma, and Coosada. Tile plantsare located in Fayette and Florence. Theannual value of clays produced in the state isabout $29 million (U.S. Geological Survey,2007a). Potential additional growth can beanticipated in Alabama because of abundantclay and shale resources in the state.BENTONITEBentonite (smectite clays), a weatheringproduct of volcanic ash, occurs near the baseof the Ripley Formation at Sandy Ridge insoutheastern Lowndes County. Nonswellingcalcium bentonite is mined from Sandy Ridgeand processed for use in agriculturalindustries and as a binder in foundry sand.Since mining began in 1964, about 5.3 millionshort tons of bentonite has been produced.The Lowndes County bentonite has highplasticity and a very high leveling strength.Since 1980, an average of 183,000 short tonsof bentonite has been produced annually,representing the only bentonite productionfrom the Selma Group in the southeastCoastal Plain Province (Hosterman, 1984;Dean, 2000). Annual production value ofbentonite is about $3.48 million (U.S.Geological Survey, 2007a). Bentonite alsohas been reported in Cretaceous deposits ofMontgomery County and from the Tertiary inClarke County.Figure 4.— Varicolored clays and shales along the contact of the Coastal Plainand Appalachian Plateaus, south of Hamilton, Marion County, Alabama.

9Table 4.--Production (short tons) of selected clays in Alabama, 2000-2007Data Sources: Modified from Alabama Department of Industrial Relations,Office of Safety and Inspection (2000-2007).Year Brick clay Fuller’s earth Common clay Bauxite Kaolin* Bentonite2007 1,159,832 782,952 1,095,810 141,914 167,585 110,6252006 1,003,520 835,419 735,476 397,986 185,679 113,4462005 746,925 851,817 302,507 133,586 185,427 124,3282004 766,735 946,696 179,263 286,458 189,943 208,5802003 896,801 775,157 151,082 150,442 210,673 243,4612002 773,669 702,246 30,144 277,378 197,969 143,5622001 850,327 883,044 24,900 273,002 195,388 254,5062000 930,423 880,400 63,070 281,852 195,388 290,801*St. Clair County.FIRECLAYFireclay is a siliceous clay rich in hydrousaluminum silicates, useful for themanufacture of refractory ceramic productssuch as crucibles and firebrick. Many of theclays that occur below coal seams(underclays) of the Pottsville Formation inAlabama commonly have refractorycharacteristics. These underclays aredistributed throughout the coal-producingareas in north-central Alabama—Blount,Fayette, Jefferson, Marion, Tuscaloosa, andWalker Counties—and can be mined inconjunction with coal. The clay that occursbelow the Mary Lee coal group in theCordova district of Walker County is used inmaking structural products, such as brick andtile. Since 1925, an estimated 6 million shorttons of fireclay has been mined from WalkerCounty with an average annual productionsince 1980 of 90,980 short tons, representingabout 38 percent of the state's refractory clayproduction (Dean, 2000). Siliceous fireclayhas also been mined in Calhoun and ShelbyCounties.KAOLINKaolin, popularly known as china clay, isthe best known of the pottery clays. It iscomposed principally of the mineral kaolinite(hydrous aluminum silicate) and has beenproduced from deposits in the Coastal PlainProvince for more than a century. Economicdeposits are associated with bauxite in theEufaula district in Barbour and HenryCounties (Clarke, 1973). Kaolin productionfrom the Eufaula district began in 1958. Since1961, about 1.8 million short tons of kaolinhas been mined from the Eufaula district foran average annual production since 1980 ofabout 55,500 short tons. Kaolin was alsomined in Marion County from 1939 to 1977,with an estimated 666,000 short tons minedfrom 1942 to 1977 (Dean, 2000). This kaolinwas used in floor and wall tiles, firebrick, andas a filler in paper and fertilizer. Kaolin is alsomined in St. Clair County for use inmanufacturing cement.FULLER'S EARTHClay suitable for the manufacture oflightweight aggregate occurs in a zone thatextends from western Wilcox County throughMarengo County and across southern SumterCounty (Clarke and Tyrrell, 1976). Fuller'searth in the Porters Creek Formation is minednear Livingston in Sumter County forproduction of lightweight aggregate.Lightweight aggregate is made from clay orshale containing carbonaceous or calcareousmaterial. Heating it to fusion temperatureproduces carbon dioxide gas, which shapesvesicles. Upon cooling, the expanded productis full of cavities. This material can be usedfor low density, or lightweight, aggregate inmaking concrete blocks. It is also used to

10make nonskid pavement and in horticulturalapplications (Hosterman and Patterson,1992).CRUSHED STONERock types in Alabama with goodphysical characteristics (loose unit mass, bulkspecific gravity, absorption and abrasionvalues) for crushed stone include limestone,dolomite, marble, granite, sandstone, andquartzite. The principal uses are inconstruction for aggregate, agricultural uses,chemical and metallurgical uses (cement andlime manufacture, flux stone), and otherspecial uses such as water treatment, minedusting, and fillers and extenders. The annualproduction of fine to coarse constructionaggregate sold or used by Alabamaproducers amounts to about 26.76 millionmetric tons with a value of $175 million (unitvalue of $6.54 per metric ton). The totalamount of all crushed stone produced in thestate in 2007 was 51.7 million metric tonsvalued at $375 million, accounting for about28 percent of the total value of mineralproduction (U.S. Geological Survey, 2007a,2008b).DOLOMITEDolomite, a carbonate rock that consistsprincipally of calcium magnesium carbonate,occurs extensively in northeastern Alabama(fig. 5). Dolomite is used to manufacture rockwool (used for insulation), in the chemicalindustry to extract metallic magnesium, inagricultural applications to condition soil, asflux, and as an alternative to limestone in theproduction of aggregate. The unit value ofcrushed dolomite is about $6.37 per metricton (U.S. Geological Survey, 2007a). Most ofthe dolomite rock units in Alabama (forexample, the Knox Group dolomites) have ahigh content of silica and other impurities,which generally preclude commercialdevelopment for most applications. TheCambrian Ketona Dolomite, however, isknown for its purity and is quarried inJefferson and Shelby Counties for a variety ofapplications. The Ketona Dolomite was minedfrom the Dolonah quarry at Bessemer from1924 to 1981 for fluxing material and was thefirst large-scale industrial quarry, producing1.1 million short tons of dolomite annually asearly as 1942. The Ketona Dolomite ispresently mined in the Dolcito quarry inBirmingham, which has been operating sincethe early 1900s. Production of dolomite fromthe Dolcito quarry exceeds 1 million shorttons annually (Alabama Department ofIndustrial Relations, 2007). Beg (1984)reported on the distribution andcharacteristics of dolomites in Alabama.GEMSTONES AND OTHER MINERALSA variety of gemstones and otherminerals which are of value to collectors ofmineral specimens occur in Alabama. Theseminerals include amethyst, beryl (emerald),calcite, fluorite, gypsum, magnetite, quartz(agate), rutile, tourmaline, turquoise, andwavellite (Cook and Smith, 1982). Also,freshwater mussel shells are exported for usein the production of cultured pearls. Sectionsfrom a mussel shell are cut out, partitioned,rounded, polished, and inserted into oystersas the pearl nuclei. After a period of time, thecultured pearl is removed from the oyster andused in jewelry production. The Tennesseeand Alabama River systems are currently themost important sources of commercialmussels (Outdoor Alabama, 2008). Theyearly value of exported shell is about$370,000 (U.S. Geological Survey, 2007a).In 1990 “star blue quartz” was designatedas the official gemstone for Alabama. Thisgemstone is asteriated (rutilated) light-bluegrayquartz from Chambers County in thesouthern Piedmont. It exhibits a bluish castwhen viewed in direct sunlight. Facetedmaterial exhibits a strong, central, six-rayedstar. The raw material consists of residualvein quartz found in a red clay soil profile(Rohrbach, 1989).GRANITEGranite is a plutonic rock composedprimarily of the minerals feldspar, quartz, andmica. Rocks with granitic mineral compositionoccur throughout the Alabama Piedmont.These granitic rocks commonly have a

Figure 5.— Generalized distribution of limestone, dolomite, and marble resources in Alabama.11

12banded texture and are termed "granitegneiss." Such stone has been quarried foruse as dimension stone and crushed stone.Granite has been quarried for crushed stoneon an intermittent basis since 1936. Granitegneiss of the Elkahatchee Quartz DioriteGneiss is presently quarried in Coosa Countyfor use as crushed stone, riprap, andaggregate. Granite is also quarried inRandolph County and was used extensivelyin construction of the R.L. Harris hydroelectricdam on the Tallapoosa River. Other granitequarries operate in Lee and Elmore Counties.Granite production currently exceeds 1 millionshort tons annually (table 1). The unit value ofcrushed granite is about $6.88 per metric ton(U.S. Geological Survey, 2007a).LIMELime is principally calcium oxide (CaO) ora mixture of CaO and magnesium oxide(MgO) produced by the calcining of limestoneor dolomite. Large-scale lime production bythe Shelby Lime Company began in the1850s near Montevallo. The major uses oflime include steel making, papermanufacture, water purification, andagricultural soil conditioning. In Alabama, theOrdovician Newala Limestone is the primarysource of raw material for the production oflime (Puckett and others, 1990). Annualproduction in Alabama is about 2.24 millionmetric tons of lime valued at about $181million (U.S. Geological Survey, 2007a).LIMESTONELimestone suitable for crushed stone andconsisting principally of calcium carbonate iswidely distributed in Alabama (fig. 5). Mostlimestone quarries in the state are open pits(fig. 6), but underground mining has beenused in Franklin, Jefferson, Marshall, andShelby Counties. The limestone units ofAlabama have a wide variety of chemical andphysical properties and are suitable forvarious applications (Beg, 1984). Limestoneof varying grade is used for flux, aggregate,dimension stone, and soil conditioner, and inmany industrial processes including themanufacture of glass, refractories, fillers,abrasives, cement, lime, and chemicals. TheMississippian Bangor and TuscumbiaLimestones are quarried throughout northAlabama. In Jefferson and Shelby Counties,the Cambrian Conasauga Formation andOrdovician Newala Limestone are extensivelyquarried (Rheams, 1992). Limestone is theleading crushed stone produced in Alabamawith an annual value of about $269 millionand a unit value of $6.56 per metric ton (U.S.Geological Survey, 2007a). Shelby County isthe state's leading limestone-producing areawith an average annual production since2000 of 19.2 million short tons, representingroughly 40 percent of Alabama's entireproduction (table 2).Chalk is a soft fine-textured variety oflimestone that occurs in the Coastal PlainProvince of west-central Alabama (figs. 2, 5).The Demopolis Chalk of the Selma Grouphas been mined for use in the manufacture ofportland cement and agricultural soilconditioner since 1900 from the Spocariquarry near Demopolis. Approximately 29million short tons of chalk has been minedfrom the Spocari quarry since 1942. Since1980, this quarry has produced 1.2 millionshort tons of chalk annually. At St. Stephensin Washington County, the Tertiary MariannaLimestone was mined from 1927 to 1980 foruse in cement. About 26 million short tons oflimestone was mined from 1942 to 1980(Dean, 2000).MARBLEIn Alabama the major source of marble—the metamorphosed equivalent of limestoneand dolomite—is in Talladega County (fig. 5),where it occurs in a narrow outcrop belt fromthe Coosa River to southeast of Talladega(Guthrie, 1989). This area is known as theSylacauga Marble belt, named for exposuresnear Sylacauga, where marble has beenquarried for more than 160 years. In theSylacauga area, marble known for its highgradecrystalline texture, whiteness, andbeauty has been extensively quarried with anestimated total production of 42 million shorttons (Dean, 2000). In 1969, SylacaugaMarble was designated as the official rock of

13Figure 6.—Quarry operation at Glenco, Etowah County, Alabama, for crushed limestone(photo courtesy of Vulcan Materials Company).Alabama. Although marble quarried in earlyoperations was used primarily for monumentsand for decorative purposes, today'soperations produce predominantly crushedmarble. Crushed marble is used in a numberof diversified applications including industrialfillers, fertilizer, aggregate, and micronizedmarble, which is shipped as a slurry for use inpaper pigment and coating. In 2007 marbleproduction was 4.4 million short tons (table1). Marble production has a unit value of$6.62 per metric ton (U.S. Geological Survey,2007a).In addition to the Sylacauga Marble, thedolomitic Chewacla Marble crops out in anumber of large isolated areas in Lee Countyand has been quarried for aggregate nearAuburn (Fousek, 2007). Dolomitic marble wasquarried as early as 1849 south of Auburnand used in lime production. Nearly 35 millionshort tons of Chewacla Marble has beenquarried since 1958, when large-scale miningfor crushed stone began (Dean, 2000).MICAMuscovite mica (hydrous potassiumaluminum silicate) is found as sheets or"books" associated with granitic pegmatitesoccurring as dikes and sills within themetamorphic and igneous rocks of theAlabama Piedmont. Mica-bearing pegmatiteshave been mined extensively in five majorareas: the Pinetucky area, Randolph andCleburne Counties; the Pyriton area, westernClay County; the Lineville area, eastern ClayCounty; the Rockford area, Coosa County;and the Dadeville area, Tallapoosa County.Large concentrations of flake mica also occuras finely disseminated flakes in mica schistsof the Alabama Piedmont (Epperson andRheams, 1984).Sheet mica is used primarily in theelectrical industry as insulation in a variety ofelectrical equipment. Scrap or flake mica isused by industry in dry-, wet-, or micronizedgroundform. Major uses of dry-ground micaare in drilling muds for the petroleum industry,

14in the manufacture of asphalt roofingmaterial, and as a filler-extender in gypsumplasterboard. Wet-ground mica is usedprincipally by the paint industry as aspecialized pigment extender. Micronizedgroundmica is used similarly as a fillerextenderin paints and plastics, and as adusting agent in the manufacture of rubberproducts. A new mica recovery operationcontinues to be active at Micaville in CleburneCounty. Scrap or flake mica produced atMicaville is used by industry in dry-, wet-, ormicronized-ground form.OCHEROcher is the clayey and unconsolidatedform of the minerals limonite and hematite,with various impurities. Ocher in Alabamaoccurs in sedimentary and residual deposits.The sedimentary deposits are found in theCoastal Plain Province in Autauga, Barbour,Clarke, Monroe, and Tuscaloosa Counties.Residual ocher occurs in the Valley andRidge Province and Piedmont Province inCalhoun, Cherokee, Elmore, Shelby, St.Clair, and Talladega Counties. Hematite usedas iron oxide pigment is mined in easternTuscaloosa County.QUARTZITEQuartzite (recrystallized or silicacementedsandstone) has been quarried atseveral sites in east Alabama and used forbuilding stone, riprap, road metal, and in themanufacture of silica brick. The CheahaQuartzite Member along the crest ofTalladega Mountain in the Alabama Piedmonthas been quarried in Clay County. Quartzitein the Weisner Formation has been quarriedin Cherokee and Calhoun Counties. TheHollis Quartzite in Lee County is presentlyused as road metal and as a filler inmanufacturing brick. Production in 2007 was59,000 short tons (Alabama Department ofIndustrial Relations, 2007).SALTSalt deposits underlie much of southwestAlabama at depths from 400 feet to greaterthan 18,000 feet. Salt seeps in Washingtonand Clarke Counties were used to producesalt intermittently during the 1800s. Largescaleproduction of salt brine began in 1952to supply a chlorine and caustic soda plant atMcIntosh in Washington County. Salt isproduced by solution mining for themanufacture of industrial chemicals.Numerous other salt structures occur deeperin the subsurface of southwest Alabama.SAND AND GRAVELAlabama has an abundance of sand andgravel suitable for most construction needsand many industrial uses (fig. 7). The mostextensive of many sand and gravel depositsdistributed throughout the state occur in theCoastal Plain Province in an area extendingfrom Dallas County through MontgomeryCounty and into Russell County. Thesedeposits have the potential for production ofhigh-silica construction sand and industrialgravel (fig. 8). Sand and gravel deposits inthe Valley and Ridge Province and theInterior Low Plateaus Province (figs. 2, 7)contain a high percentage of chert gravel,which is unsuited for most industrialapplications or as aggregate in concrete.Chert gravel can be used for road-basematerial and fill.Industrial and construction sand andgravel combined was the second leadingindustrial mineral commodity produced inAlabama during 2007, valued at $87.8 million(U.S. Geological Survey, 2008b). TheMontgomery district, located in the CoastalPlain Province of south-central Alabama, wasthe largest sand and gravel producing area inthe state during the period 2000-2007 (table3). Sand and gravel resources occurprincipally in Quaternary alluvium and terracedeposits of the Alabama, Coosa, andTallapoosa Rivers bordering Montgomery,Autauga, Lowndes, Elmore, and MaconCounties. Large-scale production of sand andgravel in the Montgomery district began in theearly 1920s. Since 2000, the Montgomerydistrict has produced about 2.2 million shorttons of sand and gravel annually, about 14percent of the entire production in Alabama(table 3).

15The leading use of construction sand andgravel in Alabama was in concrete aggregatewith a value of $36.7 million (unit value of$4.19 per metric ton). Other major usesinclude asphaltic concrete aggregate with avalue of $10.1 million (unit value of $7.34 permetric ton), road base and coverings with avalue of $1.9 million (unit value of $2.89 permetric ton), and fill sand and gravel with avalue of $2.29 million (unit value of $2.50 permetric ton). Other uses totaled $19.5 millionand include plaster and gunite sands (unitvalue of $6.27 per metric ton), concreteproducts (unit value of $7.10 per metric ton),Figure 7.— General distribution of sand and gravel resources in Alabama (Dean, 2000).

16Figure 8.—Quartz gravel aggregate.road stabilization, and water filtration (U.S.Geological Survey, 2007a). A developingindustry in Alabama is the use of offshoresand resources to renourish and restoreeroding and hurricane-damaged beaches(see Minerals Related Activity section). In thepast, small plants alone produced sand andgravel for a specific job or area. Recenttrends have been to develop large, highcapacityplants that use long-distancetransportation.SANDSTONESandstone is a medium-grainedsedimentary rock typically composed ofquartz sand grains cemented together bysilica or iron oxide and frequently containingsmall-scale sedimentary structures. ThePennsylvanian Pottsville Formation is themost widespread unit containing sandstoneand has been quarried throughout northAlabama for building stone and crushedaggregate for more than 160 years. Pottsvillesandstone was quarried as early as 1827 atTuscaloosa for building stone used in theconstruction of the State Capitol building.Pottsville sandstone has recently beenquarried in Blount, Cherokee, Marshall, andWalker Counties for building stone, sand andgravel, and crushed aggregate. TheMississippian Hartselle Sandstone of northAlabama has been used as a source ofbuilding stone and silica sand. Production in2007 was 1.7 million short tons (table 1).Recent annual sandstone production wasvalued at $7.69 million and a unit value of$5.96 per metric ton (U.S. Geological Survey,2007a).SILICONHigh-grade silica sand and gravel (greaterthan 99 percent SiO2) from Quaternaryalluvial deposits are used in the ferroalloyfurnace production of ferrosilicon and siliconmetal at plants in Selma, Montgomery, andBridgeport. Ferrosilicon is used as an additiveto steel to achieve complete deoxidization,and silicon is used as an alloying elementand as a component in silicone production.

17SULFURSulfur is produced as a by-product of gascleansingprocesses in plants operated inEscambia, Mobile, and Washington Counties.Sulfur recovery started in 1972 from southAlabama, and it is also currently recoveredfrom petroleum refineries in TuscaloosaCounty. Recent annual production of sulfur inAlabama was 236,000 metric tons valued atabout $9.42 million (U.S. Geological Survey,2006).POTENTIAL MINERAL RESOURCESA number of the state's mineral depositsare now classified as potential resourceseither because they are not presently minedcommercially or because they occur inquantity and grade unacceptable for presentcommercial operations. As knowledge of thestate's geology increases, or as economiccircumstances change, mining of theseminerals may become economically feasible.ASPHALTIC ROCKAsphalt-impregnated sandstone andlimestone of the Mississippian HartselleSandstone, Pride Mountain Formation, andTuscumbia Limestone underlie some areas ofColbert, Franklin, Lawrence, and MorganCounties in northwest Alabama. Crushedasphaltic stone was first used for pavingstreets in Florence, Alabama. Later, Alabamawas one of only three states producing nativeasphalt. For many years crushed asphalticlimestone from the Tuscumbia Limestonewas produced at the Margerum quarry inColbert County. From 1923 to 1982 about 14million short tons of asphaltic limestone wasmined from Colbert County. Renewed interestin the development of new energy resourceshas prompted investigations of these depositsas potential sources of petroleum (Wilson,1987).BARITEBarite (barium sulfate) is a colorless towhite, chemically inert nonmetallic mineralwith a relatively high specific gravity. Themajority of barite consumed in the UnitedStates is used as an additive to drilling mudfor rotary drilling of oil and gas wells. Otheruses include filler in paper, rubber products,paint, textiles, and as heavy constructionaggregate. Barite is also used as a source ofbarium in the chemical industry.In Alabama, barite occurs as epigeneticvein and breccia deposits in the OrdovicianChepultepec Dolomite, Longview Limestone,Newala Limestone, and possibly theMosheim Limestone Member of the LenoirLimestone (Hughes and Lynch, 1973). It alsooccurs in secondary residual deposits thatare weathering products of dolomites andlimestones. These deposits are situated in a13-county area that extends from BibbCounty in central Alabama to CherokeeCounty in northeast Alabama. In addition,barite occurs as a vein mineral within thePiedmont Province of eastern Alabama. Itwas mined in Alabama as early as the 1840s.Mining continued sporadically in Alabamauntil World War II, with most of the productionfrom Bibb, Calhoun, and Shelby Counties.From 1915 to 1924, 28,600 tons of barite wasmined, 80 percent of which came fromCalhoun County.COLUMBITE-TANTALITEThe columbite-tantalite (iron manganeseniobium-tantalum oxides) series of mineralswas only of mineralogical interest whendiscovered in the 1870s near Rockford inCoosa County. Detailed exploration led to thediscovery of mineralization hosted by theRockford Granite. Mining and production oftantalum concentrate in Coosa Countyoccurred during 1989-91 for the nationaldefense stockpile. There has been recentinterest in assessing the mining possibilitiesof the deposits in Coosa County. Thecolumbite-tantalite minerals are the principalsources of tantalum, which is a refractorymetal with several strategic industrialapplications.GARNETThe garnet group of minerals occurs inschists and gneisses of the PiedmontProvince in east-central Alabama. Rocks of

18the Wedowee, Mad Indian, Poe BridgeMountain, and Higgins Ferry Groups containgarnets as ubiquitous minerals in Randolph,Clay, Tallapoosa, Coosa, Elmore, and ChiltonCounties. Garnet crystals are usually wellformeddodecahedrons or trapezohedrons,ranging in size from microscopic to 0.5 inch indiameter. The larger crystals usually containinclusions of mica, quartz, and feldspar. Thesmaller crystals tend to be purer and free ofinclusions.Garnet's resistance to weathering resultsin garnet-bearing zones of heavy minerals inthe alluvial sediments associated with theTallapoosa and Coosa River systems as wellas in the coastal plain sedimentary apron onthe crystalline rocks of the PiedmontProvince. Garnets are used primarily asabrasives. The garnets occurring in themetamorphic rocks of the Piedmont Provincepossibly can be mined in areas where theschists contain up to 25 percent garnets.GOLD AND SILVERGold was discovered in Alabama in theearly 1830s. Recorded production to 1939was about 49,000 troy ounces of gold;however, probably an equal amount hasbeen mined but not reported. Gold has beenproduced from seven districts in the AlabamaPiedmont Province:1. the Chulafinnee-Arbacoochee district insouthern Cleburne and northernRandolph Counties;2. the Idaho district southwest of Pyriton inwest-central Clay County;3. the Cragford district in west-centralRandolph and east-central Clay Counties;4. the Riddles Mill district in southeasternTalladega County;5. the Goldville-Hog Mountain district innorth-central Tallapoosa County;6. the Devil's Backbone-Eagle Creek districtin Tallapoosa County; and7. the western Coosa and eastern ChiltonCounties district.More than 100 prospects and mines areknown in these seven districts (Lesher andothers, 1989).The towns of Arbacoochee, Chulafinnee,and Goldville, which developed from the goldmining rush of the 1830s, have now beenabandoned. The Hog Mountain mine inTallapoosa County was the most extensivelydeveloped gold mine in Alabama and iscredited with a total production of about24,000 troy ounces of gold.Gold mining ceased in Alabama, excepton an individual basis, during the late 1930s.Exploration of gold deposits in Alabama hasbeen carried out intermittently during the pastseveral years in the historic gold districts. In2008, gold prices exceeded $1,000 per troyounce, increasing interest in the historic golddistricts of the state.Silver deposits have not beenauthenticated in Alabama, although rumors of"silver mines" have been prevalentthroughout the state. These rumors may bebased on the occasional discovery of galenacrystals (lead sulfide). Approximately 2,600troy ounces of silver has been produced as aby-product of gold mining operations inAlabama (Cook and Smith, 1982).GRAPHITEGraphite is the most common mineralform of native, or naturally occurring, purecarbon. In Alabama, graphite generallyoccurs as disseminated flakes in themetamorphic rocks of the Piedmont Provincein the east-central part of the state. Themineral is particularly abundant in Clay,Coosa, and southeastern Chilton Counties,and the graphite-rich rock units within thesecounties form one of the largest graphitedeposits in the United States. The richestgraphite occurrences are associated withmicaceous quartzites and mica schists of thePoe Bridge Mountain and Higgins FerryGroups, which may contain up to 5 percentdisseminated graphite. The graphite-richzones occur as elongate lenses or layerswithin the rock, and their thicknesses rangefrom a few feet to more than 100 feet.Vanadium-bearing mica is commonlyassociated with graphite-rich zones.Graphite is an important commodity usedin the manufacture of electrical products and

19high-temperature refractory crucibles for themetals industry. Graphite is commonly usedas a dry lubricant or is mixed with clay to formthe "lead" of pencils.Flake graphite was mined extensively inAlabama from 1890 to 1931. During WorldWar I, graphite mining reached its peak with7.8 million pounds of graphite produced inClay and Coosa Counties in 1918 alone.Forty-three major mines and 30 processingplants were in operation during this period.From 1910 to 1929 roughly 50.8 millionpounds of graphite was produced, and from1942 to 1953 nearly 30 million pounds wasproduced. Technological advances led to thedevelopment and production of artificialgraphite, and foreign production renderedAlabama's graphite deposits subeconomic.Graphite mines in the state ceased activityafter 1953.HEAVY MINERALS"Heavy minerals" is a general term for agroup of minerals which, because of theirdurability and relatively high specific gravity,are concentrated by natural stream or marineprocesses. Small concentrations of heavyminerals, sometimes called "black sands,"occur in the sediment of most streams in thestate. Large, concentrated deposits that mayoccur in beach and offshore sand in coastalareas are important because heavy mineralscontain significant quantities of economicallyimportant and potentially critical rareelements. Some of the most commonminerals included in this group aretourmaline, which contains lithium and boron;rutile, which contains titanium; zircon, whichcontains zirconium and hafnium; ilmenite,which contains titanium; monazite, whichcontains several of the rare earth elements;and magnetite, an oxide of iron.IRON OREThe development of Alabama's steelindustry marked the beginning of theindustrial era in Alabama in the late 1800s.First efforts at iron making employed massivestone furnaces and used local "brown ironore" (limonite) and charcoal. Such furnaceswere located near Russellville (1818),Tannehill (1830), Polkville (1843), Shelby(1848), Round Mountain (1853), and atseveral other localities in Alabama. The ironindustry began to expand with the discoveryof red ore (hematite) in the Birmingham area,and the mill camps together with the miningcamps formed the basis for the present city ofBirmingham. In 1967 hematite wasdesignated as the official state mineral.Iron ore mining was once the state's mostimportant mineral industry, but now allunderground mines have ceased operationbecause higher grade imported ores areavailable. Red iron ore from the Silurian RedMountain Formation has been mined in Bibb,Blount, Cherokee, DeKalb, Etowah,Jefferson, and Tuscaloosa Counties. Browniron ore has been mined in Barbour, Butler,Calhoun, Cherokee, Chilton, Colbert,Conecuh, Crenshaw, Franklin, Jefferson,Pike, Shelby, and Tuscaloosa Counties.Brown iron ore washing and screening plantswere generally near the open-pit mine andwere moved as mining operations shiftedfrom one mine to another. In TalladegaCounty specular hematite (gray iron ore)occurs in quartzite of the Cambrian WeisnerFormation. This iron ore contains a low-grademetamorphic mineral assemblage, whichcontains pyrite and chalcopyrite. The totaliron ore production for Alabama from 1840 to1975 was about 376 million long tons (Dean,2000).Alabama has significant resources of ironore. Although most outcrop areas of themajor red ore beds have been strip mined, anestimated 4.2 billion tons of red ore underlieareas in DeKalb, Etowah, Jefferson, and St.Clair Counties. These iron ore resourcescould be mined underground if economicconditions became favorable or if it becamestrategically necessary. In addition, resourcesof brown iron ore in the southeastern,northwestern, and central counties areestimated at 925 million tons (Simpson andothers, 1978).

20PHOSPHATE ROCKPhosphatic material occurs in the CoastalPlain Province at the contact between theCretaceous Eutaw Formation and MoorevilleChalk in Perry and Dallas Counties.Phosphate occurs in nodules, grains, bonefragments, and shark teeth within a narrowsand and clay zone. This phosphatic zonerepresents only a potential reserve of lowgradephosphate.Phosphate rock has been mined fromLimestone County, but operations werediscontinued in 1983. In this area phosphaticmaterial occurs in Ordovician limestone, but itwas mined only from the residuum andweathered portions of the phosphaticlimestone. From 1978 to 1983 roughly721,000 short tons of collophane, orphosphate-bearing residuum, was mined.The residual deposits contained appreciableamounts of phosphate, but no attempts havebeen made to recover phosphate economicallyfrom the unweathered limestone.PYRITEPyrite (iron disulfide) is a common sulfidemineral in the Alabama Piedmont Province,occurring as "fool's gold" in metamorphic,igneous, and sedimentary rocks. Pyrite has avariety of uses including manufacture of ironsinter, sulfuric acid, and sulfur. Pyritedeposits in the Hillabee Greenstone in thevicinity of Pyriton, Clay County, were firstmined in the 1850s, and production of pyritefor sulfur continued intermittently until WorldWar I.SLATESlate is a compact, fine-grainedmetamorphic rock formed by the alterationand recrystallization of clay minerals insedimentary rock. Its most distinguishingfeature is a pronounced cleavage alongplanes that are independent of originalbedding. In Alabama, slate and phyllite with aslaty cleavage (will split into slabs and thinplates) crop out in parts of Shelby, Chilton,Talladega, and Calhoun Counties. Althoughslate was originally used for building stone,modern uses include industrial extenders,inert fillers, lightweight aggregate, and roadaggregate. Slate with the physical propertiesnecessary for use as roofing material hasbeen reported in Talladega County. Also,slate for building stone and other applicationshas been mined in northern Chilton andsouthern Shelby Counties.TALCTalc (hydrated magnesium silicate)occurs in association with hydrothermallyaltered dolomite of the Shady Dolomite nearWinterboro, Talladega County (Blount andHelbig, 1987). In the Winterboro area,prospecting for talc began as early as 1918,but the majority of production occurredbetween 1953 and 1976. From 1955 to 1976,the American Talc Co. mined nearly 130,000short tons of talc from this area. In 1963, aflotation mill was constructed at nearbyAlpine, where local and imported high-qualitytalc is processed for use as a filler in goodssuch as pharmaceuticals and cosmetics. Talcproduction from the Winterboro area resumedon a small scale from 1988 to 1992.TRIPOLITripoli (silicon dioxide) is a light-colored,porous, friable, sedimentary rock that resultsfrom the weathering of chert or siliceouslimestone. Commercial tripoli averages 98 to99 percent silicon dioxide with minor amountsof alumina (clay minerals), titanium, and irondioxide. Large, undeveloped deposits ofcommercial-quality tripoli occur in the upperpart of the Fort Payne Chert in westernLauderdale and Colbert Counties. The tripoliin northwest Alabama is composed ofcrystalline aggregates of quartz with generallyless than 1.5 percent impurities. Smaller,scattered deposits of tripoli occur in chertsand dolomites in Calhoun and TalladegaCounties. These deposits are composedprincipally of individual, frosted, subangular torounded quartz grains.Tripoli has excellent abrasive qualitiesand is used mainly as a component of buffingand polishing compounds. Because it ischemically inert and resists abrasion, tripoli isused as a filler and extender in paint, plastics,

21and enamels. During the mid-1960s, a smallamount of tripoli was mined northeast ofWaterloo in Lauderdale County, for use asfoundry facing or silica brick.ZEOLITE MINERALSZeolites are hydrated aluminosilicates ofalkali and alkaline earth metals and areunique in that their crystal structure containsmicropores. Zeolite minerals occur in the PineBarren Member of the Clayton Formation, thelower clays of the Porters Creek Formation,the Grampian Hills Member of the NanafaliaFormation, and the Tallahatta Formation—allin the Paleocene and Eocene deposits insouth Alabama (Beg, 1992). The zeoliteminerals identified in these formations areheulandite, clinoptilolite, and phillipsite. Themajor occurrence of zeolites is in theTallahatta Formation; zeolites have yet to beexploited commercially.The discovery of unusual properties ofzeolite minerals, particularly their ability to actas molecular sieves, their ion exchangecapabilities, and hydration and rehydrationproperties, has created a great demand forzeolites by industry. Zeolites are used topurify natural and industrial gases, and forwater filtration systems, soil conditioning,aquaculture systems, carriers of pesticides,desiccants, and many other uses requiringmolecular capillaries. At Chickasaw in MobileCounty, artificial zeolites are produced for useas molecular sieve absorbents.FURTHER READINGPublished reports on the state's geologyand mineral resources are too numerous toinclude a complete citation in this report. Acomplete list of Geological Survey ofAlabama publications can be accessed onthe Survey’s web site athttp://www.gsa.state.al.us. Also, informationon Survey publications is available from thePublications Sales Office, Geological Surveyof Alabama, P.O. Box 869999, Tuscaloosa,Alabama 35486-6999 (telephone 205-247-3636). The Geological Survey PublicationsSales Office is also a repository for U.S.Geological Survey topographic maps, whichmay be purchased. An index to topographicmaps may be obtained free of charge.The Geological Survey of Alabamareports listed below summarize informationon the state's mineral resources and may beobtained from the Publications Sales Office.Summary Report on the MineralResources of Southwest Alabama, 1986, byMirza A. Beg, Bennett L. Bearden, Otis M.Clarke, Jr., Robert L. Barnett, and ThomasW. Daniel, Jr., Geological Survey of AlabamaInformation Series 65, 33 p.Mineral Filler and Extender Resources inAlabama, 1990, by Karen F. Rheams,Geological Survey of Alabama Circular 145,77 p.Geologic Map of Alabama, 1988,compiled by Michael W. Szabo, W. EdwardOsborne, Charles W. Copeland, Jr., andThornton L. Neathery, Geological Survey ofAlabama Special Map 220 (scale 1:250,000).Geologic Map of Alabama, 1989,compiled by W. Edward Osborne, Michael W.Szabo, Charles W. Copeland, Jr., andThornton L. Neathery, Geological Survey ofAlabama Special Map 221 (scale 1:500,000).Assessment of Nonhydrocarbon MineralResources in the Exclusive Economic Zone inOffshore Alabama, 1990, by Steven J.Parker, Geological Survey of AlabamaCircular 147, 73 p.Industrial Minerals of the SoutheasternUnited States—Economic Mineral Resourcesin Central Alabama, 1990, by Karen F.Rheams and Guerry H. McClellan, GeologicalSurvey of Alabama Guidebook 3-3, 60 p.Selected Industrial Mineral ResourceSites and Processing Facilities in WestAlabama, by Karen F. Rheams, 1991,Geological Survey of Alabama Guidebook 4,56 p.Industrial Minerals of the SoutheasternUnited States—Proceedings of the 2ndAnnual Symposium on Industrial Minerals,1992, edited by Karen F. Rheams and GuerryH. McClellan, Geological Survey of AlabamaCircular 161, 111 p.In addition to these resources, onlinesources of minerals-related data, including

22current production statistics and companiesnow operating in the state, are listed in the“References Cited” section below.REFERENCES CITEDAlabama Department of Industrial Relations,Office of Mine Safety and Inspection,2007, Annual statistical report, accessedMay 30, 2008, at http://dir.alabama.gov/mr/.___2000-2006, Annual statistical reports:Montgomery, Alabama.Alabama Department of Transportation,2008, List I-1, Aggregates—Sources ofcoarse and fine aggregates, accessedMay 30, 2008, at http://www.dot.state.al.us/Docs/Bureaus/Materials+and+Tests/Testing/MSDSAR/MSDSAR_Lists.htm.Alabama Development Office, 2007, Alabama2006 new and expanding industry report:Montgomery, Alabama, 24 p.___2008, Alabama new and expandingindustry announcements, 2007:Montgomery, Alabama, 23 p.Beg, M. A., 1984, Limestone resources ofAlabama: Alabama Geological SurveySpecial Map 172 with text, 24 p.___1992, Zeolite minerals in the TallahattaFormation, Alabama: Alabama GeologicalSurvey Circular 160, 27 p.Blount, A. M., and Helbig, S. R., 1987, Talcand chlorite in the Winterboro area,Talladega County, Alabama: AlabamaGeological Survey Circular 129, 43 p.Clarke, O. M., Jr., 1973, Bauxite and kaolin inthe Eufaula bauxite district, Alabama:Alabama Geological Survey Bulletin 100,90 p.Clarke, O. M., Jr., and Tyrrell, M. E., 1976,Porters Creek lightweight aggregate:Alabama Geological Survey Circular 100,35 p.Cook, R. B., and Smith, W. E., 1982,Mineralogy of Alabama: AlabamaGeological Survey Bulletin 120, 285 p.Dean, L. S., 2000, Minerals in Alabama,1998-99: Alabama Geological SurveyInformation Series 64Q, 44 p.Epperson, R. S., and Rheams, K. F., 1984,Mica in Alabama: Alabama GeologicalSurvey Atlas 18, 63 p.Fousek, R. S., editor, 2002, The geology,mining methods, and processing ofselected industrial minerals innortheastern Alabama: AlabamaGeological Society 39 th Annual Field TripGuidebook, 123 p.___2007, Locating, permitting, and operationof construction aggregate miningoperations in Alabama: AlabamaGeological Society 44 th Annual Field TripGuidebook, 105 p.Geological Survey of Alabama, 2008,STATEMAP—Alabama Metadata Portal,accessed May 30, 2008, at http://portal.gsa.state.al.us/Portal/ptk?command=openchannel&channel=8.Guthrie, G. M., 1989, Geology and marbleresources of the Sylacauga marbledistrict: Alabama Geological SurveyBulletin 131, 81 p.Hosterman, J. W., 1984, Ball clay andbentonite deposits of the central andwestern Gulf of Mexico Coastal Plain,United States: U.S. Geological SurveyBulletin 1558-C, 22 p.Hosterman, J. W., and Patterson, S. H.,1992, Bentonite and fuller's earthresources of the United States: U.S.Geological Survey Professional Paper1522, 45 p.Hughes, T. H., and Lynch, R. E., 1973, Baritein Alabama: Alabama Geological SurveyCircular 85, 43 p.Lesher, C. M., Cook, R. B., and Dean, L. S.,eds., 1989 [reprint 1999], Gold deposits ofAlabama: Alabama Geological SurveyBulletin 136, 229 p.National Cooperative Geologic MappingProgram, 2007, accessed May 30, 2008,at http://www.gsa.state.al.us/documents/misc_gsa/Alabama.pdf.Outdoor Alabama, 2008, Freshwater musselsin Alabama, accessed June 27, 2008, athttp://www.outdooralabama.com/education/generalinfo/mussels.

23Puckett, T. M., Roberson, K. E., and Tew, B.H., 1990, High calcium deposits in theNewala Limestone: Alabama GeologicalSurvey Circular 149, 29 p.Rheams, K. F., 1992, Mineral resources ofthe Valley and Ridge Province, Alabama:Alabama Geological Survey Bulletin 147,263 p.Rohrbach, R. P., 1989, The stars fell inAlabama: Lapidary Journal, v. 42, no. 12,p.20-22, 24-26, 28.Simpson, T. A., McCarl, H. N., Hilleke, A. F.,and Hanna, H. S., 1978, Assessment ofiron ore availability in Alabama and thesoutheastern Appalachian region:Tuscaloosa, University of Alabama,Mineral Resources Institute, State MineExperiment Station, 102 p.U.S. Geological Survey, 2006, Sulfur—2005Minerals Yearbook, accessed May 30,2008, at http://minerals.usgs.gov/minerals/pubs/commodity/.___2007a, The mineral industry ofAlabama—2005 Minerals Yearbook, p.3.1-3.6, accessed May 30, 2008, athttp://minerals.usgs.gov/minerals/pubs/state/al.html.___2007b, Stone, Dimension—2006 MineralsYearbook, accessed May 30, 2008, athttp://minerals.usgs.gov/minerals/pubs/commodity/.___2008a, Alabama 2007 preliminary nonfuelmineral production data: Arnold Tanner,e-mail communication.___2008b, Mineral Industry Surveys—Crushed stone and sand and gravel in thefourth quarter 2007, accessed May 30,2008, at http://minerals.usgs.gov/minerals/pubs/commodity/.Wilson, G. V., 1987, Characteristics andresource evaluation of the asphalt andbitumen deposits of northern Alabama:Alabama Geological Survey Bulletin 111,110 p., accessed May 30, 2008, athttp://www.gsa.state.al.us/online_pubs.aspx.

Published byGEOLOGICAL SURVEY OF ALABAMAServing Alabama since 1848Berry H. (Nick) Tew, Jr., State GeologistFor additional copies write:Publications Sales OfficeP.O. Box 869999Tuscaloosa, Alabama 35486-6999205/247-3636e-mail: PubSales@gsa.state.al.usA complete list of Geological Survey of Alabama and Oil and Gas Board publicationscan be obtained at the Publications Sales Office or through our web site athttp://www.gsa.state.al.us/.As a recipient of Federal financial assistance from the U.S. Department of theInterior, the GSA prohibits discrimination on the basis of race, color, national origin,age, or disability in its programs or activities. Discrimination on the basis of sex isprohibited in federally assisted GSA education programs. If anyone believes that heor she has been discriminated against in any of the GSA’s programs or activities,including its employment practices, the individual may contact the U.S. GeologicalSurvey, U.S. Department of the Interior, Washington, D.C. 20240.AN EQUAL OPPORTUNITY EMPLOYER