<P> Vermiculite is a hydrated laminar magnesium - aluminum - iron silicate which resembles mica . It can be used for many industrial applications and has been used as insulation . Some deposits of vermiculite have been found to be contaminated with small amounts of asbestos . </P> <P> One vermiculite mine operated by W.R. Grace and Company in Libby, Montana exposed workers and community residents to danger by mining vermiculite contaminated with asbestos, typically richterite, winchite, actinolite or tremolite . Vermiculite contaminated with asbestos from the Libby mine was used as insulation in residential and commercial buildings through Canada and the United States . W.R. Grace and Company's loose - fill vermiculite was marketed as Zonolite but was also used in sprayed - on products such as Monokote . </P> <P> In 1999 the EPA began cleanup efforts in Libby and now the area is a Superfund cleanup area . The EPA has determined that harmful asbestos is released from the mine as well as through other activities that disturb soil in the area . </P> <P> Talc can sometimes be contaminated with asbestos due to the proximity of asbestos ore (usually tremolite) in underground talc deposits . By 1973, US federal law required all talc products to be asbestos - free, and today there is strict quality control in the production of talc products, separating cosmetic - grade talc (e.g. talcum powder) from industrial - grade talc (often used in friction products) has largely eliminated this issue for consumers . </P>

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