EPA 2014c), was the site of a former mine that produced vermiculite contaminated with a mixture of asbestiform amphiboles, including winchite, richterite, and tremolite
asbestos (Meeker et al.
The matrix is variably composed of quartzites, mica schist, graphite schist ad tremolite
In particular it was important to make some estimates of iron oxidation state, particularly for minerals with significant amounts of both ferrous and ferric forms, such as tremolite
(Tr) and pumpellyite (Pmp) (Tables A2 and A6).
Low-grade metamorphism of komatiites produced mineral assemblages dominated by serpentine-antigorite, chlorite, talc, tremolite
, magnesite-dolomite and magnetite.
The community experienced nearly a fourfold increase in an asbestos-related cancer during the period that Libby was the world's largest supplier of vermiculite, which contains highly toxic tremolite
Between the 1920s and 1990s, a series of companies ending with Grace, mined and processed vermiculite, which contains an asbestos known as tremolite
, at a mine located seven miles outside of Libby, Montana.
The vermiculite deposits in Libby were contaminated with a form of asbestos called tremolite
2) The different types include chrysotile, amosite, crocidolite, tremolite
, anthophyllite and actinolite.
Crocidolite is a hydrated silicate of sodium and iron, amosite is a monoclinic silicate of iron and magnesium, anthophyllite is a magnesium iron silicate of low aluminium content, tremolite
is a hydrated calcium magnesium silicate, and actinolite is a monoclinic calcium magnesium iron member of the amphibole group.
When it learned that a naturally occurring asbestos (NOA) called tremolite
had become airborne because of construction and quarrying activities, the California Thoracic Society, Tustin, sprang into action.
Talc, or hydrated magnesium silicate, is formed during the breakdown and weathering of serpentine, tremolite
, and anthrophyllite rock (1).
The ore from this mine is heavily laced with a variety of asbestos called tremolite
From our studies, we determined that the most common assemblage at Dark Ridge is olivine + talc + tremolite
+ chlorite + chromite, which indicates metamorphism in the amphibolite facies.
For 27 years, the company mined vermiculite ore contaminated with asbestos and Laced with tremolite
, a rare and hazardous form of asbestos.
The problem for Libby residents was that the vermiculite in Zonolite Mountain was laced with a particularly toxic form of asbestos called tremolite