Source Clays and Special Clays

The price of a unit of clay is US $100.00. Unit size varies depend on the clay type and you will find the unit sizes listed in the order form. Shipping charges are additional. Clay orders are shipped once a week. Extra payments for faster shipments will apply from the day of shipping not the date of payment. Please contact G.S. Premachandra at or phone 765 494 4258 or  for more information about these charges.

The clays offered by the Source Clays Project change frequently because of new acquisitions and depletion of old supplies. The Source Clays Project is always grateful for new acquisitions, particularly of clays that have become depleted. If you are able to provide access to a new source of source or special clays, please contact the curator.

The following Source Clays are completely depleted. We would appreciate information on new sources or suppliers of the following materials:

  • CorWa-1 Corrensite, Packwood, Washington (Ohanapecosh Form.) Altered Eocene tuff, containing 25-50% corrensite; quartz and plagioclase impurities separable by wet sedimentation.
  • NG-1 Nontronite, Hohen Hagen, Germany, Nontronite-cemented sand (15-20% nontronite), easily separated by wet sedimentation (Char. by Schneiderhoehn, Tschermaks Min. u. Pet. Mitt., 10, 385-399, 1965).
  • SepNev-1 Sepiolite, Two Crows, Nevada (pub. ref Clays and Clay Minerals, v. 26, p. 58-64, 1978).
  • VTx-1 Vermiculite, Llano, Texas, USA, a mixture of magnesite, phlogopite, and vermiculite. The vermiculite can be separated by hand picking.
  • SAz-1 Ca-Montmorillonite (“Cheto”) in natural chunk form, Apache County, Arizona, USA
  • SCa-3 (50 grm/unit) Montmorillonite (“Otay”), Otay SanDiego County, California. USA
  • IMt-1 Illite, Silver Hill, Mont. (Cambrianshale) I Md. Char.By Hower, et al.,Amer. Min. 51, P 825-854, 1966