Asbestos Fibers and Other Elongate Mineral Particles: State of the ...
Asbestos Fibers and Other Elongate Mineral Particles: State of the ...
Asbestos Fibers and Other Elongate Mineral Particles: State of the ...
- No tags were found...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Table 2. Definitions <strong>of</strong> specific minerals<br />
146<br />
Glossary <strong>of</strong> Geology, 5th ed.<br />
[American Geological Institute 2005] Leake et al. [1997] NIOSH [1990a]<br />
Dictionary <strong>of</strong> Mining,<br />
<strong>Mineral</strong>, <strong>and</strong> Related Terms<br />
[U.S. Bureau <strong>of</strong> Mines 1996]<br />
[Note: Footnotes identify <strong>the</strong> Primary<br />
Source Citation for <strong>the</strong> definition]<br />
Term<br />
Actinolite can occur in both <strong>the</strong><br />
asbestiform <strong>and</strong> nonasbestiform<br />
mineral habits <strong>and</strong> is in <strong>the</strong> mineral<br />
series tremolite-ferroactinolite. 1<br />
The asbestiform variety is <strong>of</strong>ten<br />
referred to as actinolite asbestos.<br />
A monoclinic calcic amphibole<br />
intermediate between<br />
ferroactinolite <strong>and</strong> tremolite:<br />
Ca2(Fe,Mg) 5Si8O22(OH) 2;<br />
with Mg/(Mg+Fe2+ ) between<br />
0.5 <strong>and</strong> 0.9 (o<strong>the</strong>rwise if ≤<br />
0.5 it is ferroactinolite, <strong>and</strong><br />
if ≥ 0.9 it is tremolite).<br />
A bright-green or grayish-green monoclinic<br />
mineral <strong>of</strong> <strong>the</strong> amphibole group:<br />
Ca2(Fe,Mg) 5(OH) 2[Si8O22]. It may contain<br />
manganese. It sometimes occurs in <strong>the</strong> form<br />
<strong>of</strong> asbestos, <strong>and</strong> also in fibrous, radiated, or<br />
columnar forms in metamorphic rocks (such<br />
as schists) <strong>and</strong> in altered igneous rocks.<br />
Actinolite A monoclinic mineral,<br />
2[Ca2(Fe,Mg) 5Si8O22(OH) 2];<br />
in <strong>the</strong> hornblende series Mg/<br />
(Mg+Fe2+ ) = 0.50 to 0.89 <strong>of</strong> <strong>the</strong><br />
amphibole group; forms a series<br />
with tremolite; green, bladed,<br />
acicular, fibrous (byssolite<br />
asbestos), or massive (nephrite<br />
jade); prismatic cleavage; in<br />
low-grade metamorphic rocks.<br />
Amosite is <strong>the</strong> commercial<br />
term derived from <strong>the</strong> acronym<br />
“<strong>Asbestos</strong> Mines <strong>of</strong> South Africa.”<br />
Amosite is in <strong>the</strong> mineral series<br />
cummingtonite-grunerite, 1 in<br />
which both asbestiform <strong>and</strong><br />
nonasbestiform habits <strong>of</strong> <strong>the</strong><br />
mineral can occur. This mineral<br />
type is commonly referred<br />
to as “brown asbestos.”<br />
A commercial term for an iron-rich,<br />
asbestiform variety <strong>of</strong> amphibole occurring<br />
in long fibers. It may consist <strong>of</strong> an<br />
orthorhombic amphibole (anthophyllite<br />
or gedrite) or <strong>of</strong> a monoclinic amphibole<br />
(cummingtonite or grunerite).<br />
Amosite 1. A monoclinic mineral in <strong>the</strong><br />
cummingtonite-grunerite series. 2<br />
2. A commercial asbestos<br />
composed <strong>of</strong> asbestiform gedrite,<br />
grunerite, or anthophyllite<br />
<strong>of</strong> <strong>the</strong> amphibole group;<br />
has typically long fibers.<br />
A macroscopically lamellar brown to green<br />
monoclinic serpentine mineral, which consists<br />
structurally <strong>of</strong> alternating wave forms<br />
in which <strong>the</strong> 1:1 T-O layer reverses sides<br />
<strong>and</strong> direction <strong>of</strong> curvature at each wave null<br />
point. In most specimens <strong>the</strong> repeat distance<br />
<strong>of</strong> <strong>the</strong> wave pattern measures between<br />
25.5 <strong>and</strong> 51.0 Å: (Mg, Fe2+ ) 3Si2O3(OH) 4.<br />
Antigorite A monoclinic mineral,<br />
(Mg,Fe) 3Si2O5(OH) 4; kaoliniteserpentine<br />
group; polymorphous<br />
with clinochrysotile, lizardite,<br />
orthochrysotile, parachrysotile;<br />
greasy variegated green;<br />
used as an ornamental stone.<br />
See footnotes at end <strong>of</strong> table. (Continued)<br />
NIOSH CIB 62 • <strong>Asbestos</strong>