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    Very Fine Gemstone: Bicolor Tourmaline - 57.75 Ct.
    Keffi, North Central Area, Nigeria

    Few gem materials will show two or more distinct colors in the same specimen. Tourmaline is one of the minerals that can, and does, appear as multi-colored crystals. The Angwan Tudu #4 pegmatite is likely to be the specific source for this stunning bicolor gem that weighs a whooping 57+ carats. Grading from an orangey-pink at one end, the octagonal step cut gem abruptly transitions near the middle to a bright yellowish-green. The transition zone is free from the stress related inclusions commonly seen in bicolor gems and, in fact, the whole stone is eye clean and flawless. The AGL Cert (# CS 65957) that comes with the stone indicates that it is entirely natural and free from signs of any treatments or enhancements. Large, natural bicolor Tourmalines with this level of perfection are few and far between.
    Measurements: 29.47 x 16.61 x 11.75 mm, 57.75 cts.
    Offered at no reserve.

    Provenance: Rainbow of Africa Collection
    Accompanied by AGL Certificate # CS 65957

    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.

    Auction Info

    Auction Dates
    October, 2015
    15th Thursday
    Bids + Registered Phone Bidders: 5
    Lot Tracking Activity: N/A
    Page Views: 2,831

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