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    Dallas Gem Mine (Benitoite Mine; Benitoite Gem Mine), New Idria District, Diablo Range, San Benito Co., California, USA

    Now that the sole source of decent Benitoite has been closed, the situation is very like when a noted artist stops producing: the supply becomes limited. Mineral localities that are sole sources for certain things are exactly the same. Benitoite: the Über-rare Barium Titano-Silicate is essentially a one-locality mineral, based on size and perfection of extant examples. Joaquinite is almost as rare and the best examples of Joaquinite are still from the Dallas Gem mine, the type locality. This charming matrix specimen features all three of the minerals for which this deposit is famous: Benitoite, Joaquinite, and Neptunite. All of the Benitoites show the classic ditrigonal, dipyramidal form that is unique to this mineral, along with typical variation in color from colorless in the center portions to transparent, sapphire-blue at the tips of the crystals. The seven Benitoites measure up to .88 inch (2.1 cm) on edge, and with the exception of one crystal that appears to be repaired, are in excellent condition. Luster is the typical satin to glassy one and fluorescence is the typical blue-white one as well. Perched on a small knob of white, massive Natrolite is a Joaquinite of average size (˜ 2 mm) that appears to be twinned along with a number of shiny black Neptunites up to ˜ 4 mm in length. All things considered, this is an excellent miniature example of the combination of rare minerals most sought after by sophisticated collectors.
    Overall measurements: 1.7 x 1.95 x 1.55 inches (4.3 x 5 x 3.9 cm).

    Provenance: Keith Proctor [Hoppel # D0060]

    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: 0
    Lot Tracking Activity: N/A
    Page Views: 1,081

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