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    Description

    CUPRITE

    Very Fine Gemstone: Cuprite - 293.60 Ct.
    Onganja Mine, Onganja, Seeis, Windhoek District, Khomas Region, Namibia

    A long time ago (1973), in a continent far, far away (Africa), miners bent on extracting Copper ore in massive quantities broke into a series of open fissures along a vein system, deep within the underground workings of the Onganja Mine in Namibia. These cavities were lined with stout, green crystals with blood red, transparent interiors. It was quickly determined that the cores were composed of the pure Copper oxide mineral: Cuprite, over-coated with green Malachite. As ubiquitous as Copper minerals are, very few localities ever produce transparent Cuprite crystals of any size, much less monsters big enough to cut the almost 300 carat behemoth seen here. It is larger than the one held by the Smithsonian, which weighs 203.75 carats, as well as any others held by public institutions. A 299.5 carat stone is reputed to be in a private collection, but we cannot verify this. The triangular, modified brilliant cut gem offered here has been examined by the American Gemological Laboratories (Cert # 65970) and certified as "Natural Cuprite" with "Deep Red" coloration that is most visible in transmitted light. With a refractive index quite a bit higher than Diamond (2.849 vs. 2.419) this Cuprite shows an exotic, almost metallic luster that is very distinctive. It was cut by Mike Gray: master rare stone cutter of Missoula, Montana.
    Measurements: 39.67 x 37.55 x 20.40 mm, 293.60 cts.
    Offered at no reserve.

    Provenance:
    Rainbow of Africa Collection
    Accompanied by AGL Certificate # CS 65970




    Condition Report*: Condition report available upon request.
    *Heritage Auctions strives to provide as much information as possible but encourages in-person inspection by bidders. Statements regarding the condition of objects are only for general guidance and should not be relied upon as complete statements of fact, and do not constitute a representation, warranty or assumption of liability by Heritage. Some condition issues may not be noted in the condition report but are apparent in the provided photos which are considered part of the condition report. Please note that we do not de-frame lots estimated at $1,000 or less and may not be able to provide additional details for lots valued under $500. All lots are sold "AS IS" under the Terms & Conditions of Auction.

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    Auction Dates
    October, 2015
    15th Thursday
    Bids + Registered Phone Bidders: 4
    Lot Tracking Activity: N/A
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