Diatomaceous earth occurs in post-glacial lake deposits exposed along the shore of Cook Inlet north of the village of Kenai, Alaska. Diatomaceous earth is an unconsolidated earthy deposit formed by accumulation of the minute siliceous tests (skeletons) of diatoms, a type of algae. Diatomaceous earth is sometimes referred to as diatomite.
The largest and purest of these deposits was mapped and sampled in detail. The diatomaceous earth attains a maximum thickness of 12 feet, with the dried material averaging between 65 and 75 percent diatoms by weight.
The deposit mapped contains about 200,000 cubic yards of diatomaceous earth which is readily accessible, and is favorably situated with regard to transportation by sea and road.