October 22, 2003
Diatomaceous earth, the pinkish white outcrop shown above (near Lovelock, Nevada), is a mineral of plant origin. It represents the accumulation of an enormous number of fossil diatoms (single-celled plants). It's also known as diatomite or kieselguhr, and it's referred to as white dirt by miners -- in bright sunlight it can be almost as white as new snow. Diatomite has several unique characteristics. Because of its lightness, porosity, and its honeycombed structure, it's an ideal filtering medium. In addition, it's inherently stable and devoid of most trace elements. Thus, diatomite is ideal for use by processors who have very high purity requirements such as the food, beverage and pharmaceutical industries.
There are many deposits of diatomaceous earth in the world, but only a few of them are both pure enough and large enough to serve as a source of raw material for the production of filter aids. Two of these deposits are in Nevada and Oregon -- among the finest in the world.