1948: What the Government Knew about Libby, Montana Vermiculite and Amphibole Asbestos

I found the 1948 book titled Talc, Graphite, Vermiculite, and Asbestos in Montana on eBay a week or so ago. The book was published by Montana School of Mines/State of Montana Bureau of Mines and Geology. Interestingly, I see that the Montana Bureau of Mines and Geology will still sell the book in an electronic format for $7, although my message last week to the department hasn’t yet been returned. If you would like a complete electronic copy, best if you contact them to arrange payment and delivery.

I have to say that the short discussion on the book page 26 stating the “extensive studies on concentration, processing, and utilization are being continued” when discussing vermiculite is puzzling. It would seem that by 1948, with the knowledge that the vermiculite was combined with tremolite asbestos, any such testing or study would have involved fibers and air circulation studies for the protection of the miners and, in general, the town and local residents. Perhaps this was a tragic “miss” by the governmental that will forever keep the name of Libby, Montana in the same conversation as some Eternit plants, Wittenoom, Australia, and various blue asbestos mines in South Africa.

So, as of 1948, here is what the government knew:

1. The primary use of vermiculite was in heat, cold, and sound insulation (p 23);

2. Vermiculite was an unusual mica-like material that received its name from its peculiar property of expanding and opening into worm-like forms when heated to red heat. The word “vermiculite” in Latin is vermiculari, defined as bread worms (p 23);

3. As of 1948, vermiculite was not an essential product. For its use as an insulator, vermiculite had a lot of competition such as rock wool and other materials (p 23);

4. As to the history of vermiculite near Libby, “The vermiculite deposit near Libby Montana, recognized as such in 1918, is the first to be worked in the United States successfully on a large commercial scale; and development of this product, beginning in 1923, marked the initiation of a new industry not only in this state but in the nation.” Further, other locations in Montana, other states, and internationally competed to mine and sell vermiculite. The book states, “Considerable vermiculite has been mined and shipped from Colorado and Wyoming” The Colorado vein was discovered in 1913. Also see North Carolina and Pennsylvania dealing with vermiculite as early at 1873 (p 23); and

5. The Libby vermiculite was heavily mixed with the amphibole asbestos known as tremolite. In fact, sample testing showed 75% amphibole asbestos combined with 10% of vermiculite, with the remainder being pyroxenite and apatite. (p 40). Another sample was 50% tremolite and 20% vermiculite. (p 41) The asbestos wasn’t commercialized from the Libby area as the fibers were a small tonnage and low in quality. (p 41). The vermiculite, on the other hand, became big business.

As continued in the book:

The deposits, discovered in about 1915, were soon investigated by Mr. E. N. Alley who, seeing the commercial possibilities of the expanded material, experimented with the processing and utilization of the vermiculite, and he devoted time to promoting its development, a difficult task because the material was so little known. However, the Zonolite Company was eventually formed, and commercial production on a small scale began in 1925 from material taken from shallow open-cut workings. The vermiculite was expanded in a small expansion plant which had been erected at Libby in about 1922.

In addition, a lot of research was being undertaken on vermiculite. As stated in the book, “Extensive studies on concentration, processing, and utilization are being continued.” (p 26, see below)

I am new to the story about the devastation caused to Libby by vermiculite and tremolite asbestos, but it seems that as of 1948, Montana recognized that the vermiculite was a potentially strong industry. It would also have made sense, with the need to separate the combination of tremolite with the vermiculite in the mining process, that the studies focusing on concentration, processing, and utilization should have included information relevant to potential hazards when mining and processing the ore. I am not aware of any details on those studies as of 1948, but they would be interesting to see.

Let me know either in the comments section or by email to TheAsbestosBlog@gmail.com if you have any questions or comments. Thanks. Marty.