Rio Tinto | Minerals and Metals for the world

Don't I use that on my African violets?
The phrase sticks in my mind. I was being quizzed by an immigration official at a US airport who asked me what I did for a living. I replied: "Minerals Consultant dealing with materials such as vermiculite."

"Don't I use that on African violets?" came the immediate, memorable, reply. It was apparently the only use that the official knew for this versatile mineral.

Well, vermiculite has a lot more uses than with African violets, but before we get to that a little background is required.

Vermiculite gets its name from the Latin Vermiculus which means little worm: when the mineral is rapidly heated it expands and wriggles, wormlike. The first mention of vermiculite in scientific literature comes from Thomas Webb in 1824 in the American Journal of Science and he mistakenly believed that it was a member of the talc family.

However, it had been known in Japan before this time as a children's novelty because of its squirming behaviour when placed in a flame.

Resembling mica in appearance, vermiculite is a member of the phyllosilicate group of minerals, and it is found in various parts of the world, with the largest commercial operation being Rio Tinto's Palabora mine which is located at Phalaborwa in the Limpopo Province of South Africa. Vermiculite is produced by open cast mining with the resulting crude mineral flakes being from 0.25 to 8mm in size.



Don't I use that on my African violets? The phrase sticks in my mind. I was being quizzed by an immigration official at a US airport who asked me what I did for a living. I replied: "Minerals Consultant dealing with materials such as vermiculite." "Don't I use that on African violets?" came the immediate, memorable, reply. It was apparently the only use that the official knew for this versatile mineral. Well, vermiculite has a lot more uses than with African violets, but before we get to that a little background is required. Vermiculite gets its name from the Latin Vermiculus which means little worm: when the mineral is rapidly heated it expands and wriggles, wormlike. The first mention of vermiculite in scientific literature comes from Thomas Webb in 1824 in the American Journal of Science and he mistakenly believed that it was a member of the talc family. However, it had been known in Japan before this time as a children's novelty because of its squirming behaviour when placed in a flame. Resembling mica in appearance, vermiculite is a member of the phyllosilicate group of minerals, and it is found in various parts of the world, with the largest commercial operation being Rio Tinto's Palabora mine which is located at Phalaborwa in the Limpopo Province of South Africa. Vermiculite is produced by open cast mining with the resulting crude mineral flakes being from 0.25 to 8mm in size.
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Review is published by Rio Tinto, 6 St James' Square, London SW1Y 4LD, England Telephone +44 (0)20 7930 2399 Editor: Cherry DeGeer