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    Description

    RARE GEMSTONE SET: PREHNITE ROUGH & CUT
    Merelani Hills (Mererani), Lelatema Mts, Arusha Region, Tanzania
    Prehnite is a phyllosilicate of Calcium and Aluminum that most often forms as stalactitic or botryoidal aggregates. It was first described in 1789 by Hendrik Von Prehn and is the first mineral to be named in the honor of its discoverer. Rarely transparent enough to be used as a gemstone, it exhibits a vitreous to pearly luster with a hardness of 6 to 6.5 on the Mohs scale. This unusual rough and cut set is from a small find in Tanzania and the gemstone cutter was able to find a large enough piece of rough to facet a light yellowish-green sleepy 3.97 carat round Portuguese-cut gemstone that measures 10.96 mm in diameter. There are several inclusions, one of which is a dark spot on the edge of the pavilion while another one is a veil near the girdle - not unusual for Prehnites. Accompanied by a matching mineral specimen from the same locality to show its original form, this rough and cut set is in fine condition.


    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. Heritage does not guarantee the condition of frames and shall not be liable for any damage/scratches to frames, glass/acrylic coverings, original boxes, display accessories, or art that has slipped in frames. All lots are sold "AS IS" under the Terms & Conditions of Auction.

    Auction Info

    Auction Dates
    June, 2011
    12th Sunday
    Bids + Registered Phone Bidders: 1
    Lot Tracking Activity: N/A
    Page Views: 1,434

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