________________________________________________________________ INFRARED ACTIVE ALTERATION MINERALS ATHABASCA BASIN Figure 72 - The common alteration minerals found in the Athabasca Basin deposits include dravite (magnesi<strong>of</strong>oitite Mg end member), illite, kaolinite and dickite. Figure 73 - Chlorites found in the Athabasca suite. Mg-chlorite and the unique sudoite are plotted. 58 Figure 74 - Other minerals observed are quartz, hematite, monazite (REE), dolomite and siderite.
________________________________________________________________ DISCUSSION Starting with the PIMA, it took about four hard years to introduce the technology to the industry. It was very alien to users initially, as most universities do not teach infrared analytical methods. Those that do, usually treat the subject very briefly, as most departments do not have expensive infrared instrumentation. Once applications, case studies, spectral libraries, some simple mineral identification s<strong>of</strong>tware, and a well-documented training course and manuals were developed, it became easier to sustain the method. As more and more companies utilized the technology, word spread via the "grapevine". Most companies would not cite PIMA analyses in their public presentations and papers. They all considered reflectance <strong>spectroscopy</strong> their "secret weapon". With the introduction <strong>of</strong> the TerraSpec, some <strong>of</strong> the secrecy has dissipated and companies are more willing to acknowledge the application <strong>of</strong> reflectance <strong>spectroscopy</strong> to their exploration programs. Additionally, VNIR analysis has been used for over 10 years and is no longer so exotic. Spectroscopy is used for <strong>field</strong> and core reconnaissance, core logging, target generation, vectoring, blast hole logging, and remote sensing ground truth. It has its biggest successes in epithermal gold systems, porphyry, IOCG, skarns, kimberlites and unconformity uranium. Reflectance Spectroscopy has changed the way exploration is done, how core is targeted, drilled and logged and alteration systems modeled. It has made some impact on mine metallurgy, grade control and production. It has opened the important world <strong>of</strong> alteration mineralogy to a rapid, non-invasive, identification <strong>of</strong> alteration minerals in-situ and instantly, in the <strong>field</strong>, in the core shack, on the pit benches and faces and underground in the tunnels. It has expanded the geologist’s knowledge about the minerals in alteration systems, their associations, and the environments in which they form, therefore leading to a better and more predictive understanding <strong>of</strong> mineral deposits. Now, clays, phyllosilicates, and carbonates, minerals that have similar physical appearances and have always been difficult to identify by hand lens, are known in 3, 5, or 10 seconds. This analysis can be in-situ in the <strong>field</strong>, at the outcrop, and/or in the core shack. Reflectance <strong>spectroscopy</strong> has been used by all the major and many smaller companies in some capacity. There are nearly 400 instruments in the industry between the different manufacturers. Following is a partial list <strong>of</strong> companies who own or have owned spectrometers and many have more than one (apologies to those left <strong>of</strong>f the list) : Alamos Gold, Almaden, <strong>An</strong>glo American, <strong>An</strong>glo-Gold- Ashanti, Barrick, BHP, Balkan Minerals, Battle Mountain, Billiton, Bolnisi, Buenaventura, Codelco, Collahausi, Cornerstone, CRA, Crystallex, Cyprus, De Beers, Depromisa, El Dorado, Formicruz, Gencor, GoldCorp, Gold<strong>field</strong>s, Gryphon Gold, Hecla, Hemlo, Homestake, Hochschilds, Iamgold, Incor, Inmet, 59
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