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    Dallas Gem Mine (Benitoite Gem Mine), San Benito River Headwaters Area, New Idria Dist., Diablo Range, San Benito Co., California, USA

    Neptunite from the Dallas Gem Mine is, besides Benitoite, the most desirable of the rare minerals from this unique deposit. The epitome of Neptunite specimens is a single, double terminated prism perched upon contrasting, pure white Natrolite. That is exactly what we have here: a single black, doubly-terminated Neptunite crystal 1.25 inches (3.1 cm) in length, with brilliant luster, sitting on top of a white Natrolite matrix. There is a contact or tiny nick on the back of the Neptunite but this is not visible when viewed from the front. The backside shows traces of the typical "Crossite" Glaucophane matrix often seen with this material. Now that the locality is exhausted, any "new" material will be coming from old collections like this one.
    Overall measurements: 1.25 x 1.25 x .5 inches (3.2 x 3.2 x 1.3 cm).

    Provenance: Attard Minerals [Hoppel # D0030]

    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
    October, 2013
    19th-20th Saturday-Sunday
    Bids + Registered Phone Bidders: 1
    Lot Tracking Activity: N/A
    Page Views: 1,534

    Buyer's Premium per Lot:
    25% on the first $100,000 (minimum $14), plus 20% of any amount between $100,000 and $1,000,000, plus 12% of any amount over $1,000,000 per lot.

    Sold on Oct 19, 2013 for: Sign-in or Join (free & quick)
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