Recently there have been several newspaper articles, a three-part NPR series, and a 20/20 show about asbestos contamination at the former WR Grace vermiculite mine located in Libby, Montana.
Most of these articles have mentioned the fact that this problem was not inherent in all vermiculite mines, but a problem of that particular mine in Libby, Montana, because of its unique geological formation and location. Vermiculite itself does not contain asbestos, it was just the Libby, Montana, mine that was contaminated because of the presence of a very unstable secondary mineral called diopside. As a result of these articles and news stories, however, many people have become confused and concerned about vermiculite in general.
One reference for more information on this issue is: www.schundler.com/verm-asb.htm.
Down Under Thunder,
Thanks for the information, Down Under. I stand corrected. Vermiculite is a very convenient ingredient to use in planting mixes so this comes as good news.
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