Analysis of Vermiculite

Discovered in 1824, vermiculite is a mineral primarily made of hydrated iron, silica and magnesium that expands when heated. It is found around the world, and has industrial purposes ranging from building to agriculture.

Features

Vermiculite is brown to bronze yellow in color and belongs to the monoclinic crystal system, the largest crystal system. Vermiculite expands 20 times beyond its original dimensions when heated to 570 degrees Fahrenheit.

Function

Before it can be used for any of its known uses, vermiculite is heated. After it has been heated vermiculite is used in soil conditioner, acoustic insulation, thermal insulation, in concrete, in plaster, medium for starting seeds and a packing medium. It is also used as a extender or filler for plastic, paper and paint.

Sources

The main deposits of vermiculite are found in Brazil, Japan, Zimbabwe, Australia, China, Russia, South Africa, and in the United States. In the U.S. it is mainly found in Virginia, Montana, Nevada, North Carolina, South Carolina, Wyoming, Colorado and Texas.

Chemistry

Vermiculite is hydrated magnesium iron aluminum silicate hydroxide. The chemical formula for vermiculite is (Mg,Fe,Al)3(Al,Si)4O10(OH)2 - 4H2O .

Formation

Vermiculite forms from the weathering or altering of the two minerals phlogopite and biotite.

References

• The Free Dictionary: Vermiculite
• Encyclopedia Britannica: Vermiculite
• Mindat.com: Vermiculite

Resources

• Mineral Information Institute: Vermiculite
• The Mineral: Vermiculite
• The Monoclinic System