The Black Rock Desert playa dust consists primarily of silica and organic materials. One soil analysis revealed the following composition:

Silicon dioxide (silica): 43.1%

Organic matter and loosely bound water: 25.4%

Aluminium oxide: 11.8%

Iron oxide: 5.32%

Calcium oxide (quick lime): 4.51%

Magnesium oxide (magnesia): 3.46%

Potassium oxide: 2.82%

Sodium oxide: 2.29%

Titanium dioxide: 0.49%

Phosphorus pentoxide: 0.19%

Manganese oxide: 0.08%

From:

Toward a Silicate-Based Molecular Nanotechnology by Stephen L. Gillett

Dept. of Geological Sciences
Mackay School of Mines, University of Nevada
Reno, Nevada 89557 USA