The Rock Creek district sapphire deposits occur in debris flow, colluvium, and secondary alluvial deposits (figure 2). Although the bedrock for these deposits has not yet been defined, Potentate plans further geological mapping and geophysical surveys in the near future to uncover these sources.
To date, the rough sapphires recovered from the bulk sampling pits range in size from 0.25 ct to over 20 ct. Approximately 15% of this rough occurs naturally in marketable colors, including pink, orange, orange-pink, lavender, golden yellow, blue-green and green, and fine blue (figure 3). A substantial percentage of the remaining rough responds very well to heat treatment technologies that improve clarity and turn greenish and grayish rough to desirable colors such as blue, orange, yellow, pink, and parti-color.
The high-grade concentration of the sapphires recovered from the various test pits, and the substantial inferred rough sapphire resource on Gem Mountain, indicate that Potentate would be able to provide a long-term, consistent supply of sapphire rough to the global market (figure 4). Potentate would be the only large-volume source for the Rock Creek sapphires. The company is developing a marketing strategy that would provide sustainable supply chain guarantees to their clients. These clients including wholesale gemstone cutters, polishers, and fine jewelry retailers would in turn be able to provide guarantees of origin and the presence (or absence) of any heat treatment to their consumers.
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