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A number of small but rapidly growing markets exist for high purity, highly processed clays with unusual physical and chemical properties. Perhaps best known, is the "hectorite" produced by N.L. Industries from a deposit near Hector, California. This is the source material for their Bentone organophillic clay products. Surprisingly, it is also a blending clay used by many other producers to enhance their product quality. Another important clay resource is the Cheto Bentonite. Presently this is the only source of desiccant grade clay in the USA able to meet the military specifications for water adsorption. Also, the clay can be treated to produce an exceptionally high quality acid activated bentonite for clarifying edible oils. These unusual mineral resources were largely overlooked by commodity clay products until the slump in the benotite markets forced a search for new higher value products. Entering this market required a source of clay, which to date has been difficult to find. Despite intensive exploration programs these specialty clay deposits proved elusive. Locations of these unusual clay minerals are not well documented in the literature while those that were generally proved unsuitable for many higher value applications. Common problems included; contamination by metals such as lead, mercury, and arsenic, poor color, or association with undesirable gangue minerals such as calcite, dolomite, and magnesite.As difficult, particularly in the southwestern USA, where land use conflicts with National Parks, Wilderness Study Areas, and federal and state land use management agencies. Since the economic importance of these clay deposits were not recognized, they were not excluded from these restrictive land use classifications. Despite the problems the search continues. The clay resources at some domestic operations are rapidly being depleted. Foreign sources are a possibility, hut the best samples to date were obtained from locations in central Asia and eastern Africa, tenuous sources of supply distant from consuming markets. Samples submitted from Greece show potential, but uncertainties over trade policies arid future political alignments are strong barriers to investment. The demand for specialty clays, clay desiccants arid acid—activated clays continues to grow rapidly throughout the world. Customers continue to demand higher quality more efficient products fuelling the search for excellence in the clay raw materials industry.
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