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    Neptunite & Benitoite Plate
    California State Gem Mine (Dallas Gem Mine; Benitoite Mine; Benitoite Gem Mine; Gem Mine)
    Santa Rita Peak, New Idria Mining District
    San Benito Co., California, USA

    Given that the commonly associated minerals Neptunite and Benitoite rarely occur in large quantities, a plate like this absolutely colossal example weighing some 43 pounds (19.5 kg) certainly must be considered unusual, enormous and museum worthy. Numerous jet-black crystals of lustrous Neptunite accompanied by a number of well-formed, cornflower bluish crystals of Benitoite have been painstakingly revealed, by expert preparation, and now rest atop a beautiful white blanket of snowy Natrolite. The visual contrast between the colorful crystals and the stark background is, indeed, striking, and its sheer size, natural appeal and incredible surface coverage of crystals make this assuredly one of the larger pieces ever to come out of the famed locality for which the collectible black and blue minerals are so well known. This monstrous specimen surely belongs in a museum, and its numerous crystals of both good size and exceptional form of both Neptunite and Benitoite cannot be overlooked.
    Overall Measurements: 18.90 x 16.93 x 3.15 x inches (48.00 x 43.00 x 8.00 cm)

    Provenance: The Jena Blue Collection

    [Scale: 1 inch, with mark at 1 cm]

    Estimate: $20,000 - $30,000.

    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

    Bidding Begins Approx.
    24th Monday
    Auction Dates
    13th-14th Sunday-Monday
    Proxy Bidding Begins Approx.
    80 Days
    Bids + Registered Phone Bidders: N/A
    Lot Tracking Activity: N/A
    Page Views: 173
    Auction Type
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