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    "Gem" Ammonite in Matrix
    Placenticeras costatum
    Late Cretaceous
    Bearpaw Formation
    Alberta, Canada

    Ammonites were prolific during the Mesozoic Era, especially the Cretaceous Period, and all varieties of the unique cephalopod went extinct at the same time as the Dinosaurs, some 65 million years ago. An extremely small percentage of Ammonites, from virtually a single locality, are preserved in the special way as this spectacular specimen whereby the original shell material has turned to colorful Ammolite which is both a fossil and a gemstone. The iridescent colors result from light being reflected through stacked mineral layers on the outer section of the ancient shells. Such a phenomenon is rare indeed.
    This "Gem" Ammonite in a natural shale matrix exhibits brilliant iridescence and features a myriad of vibrant colors across various sections of the fossilized shell. Purples, greens, blues and golds populate the smaller smooth end of the piece, while golds, oranges and reds dominate the wide portion. While color is clearly the most noticeable characteristic of this remarkable piece, the fossilized Placenticeras costatum Ammonite from the Bearpaw Formation of southern Alberta, Canada has a very pronounced ridge in the middle of the preserved shell likely due to sediment fill during the original compression of the fossil in the shale layers from which it was mined. The added relief of the ridge protruding up from the shell gives another dimension to the already striking piece. The colorful shell of the Ammonite has a maximum diameter of 10.5 inches (26.67 cm). The matrix specimen weighs in excess of 100 lbs. (45 kg), and the sizable natural Canadian treasure comes with a Certificate of Authenticity validating its details.
    Overall Measurements: 26 x 26 x 5 inches (66.04 x 66.04 x 12.7 cm)
    Stand shown in image for photo purposes only. Specimen does not come with a base.

    [Scale: 18 inch, 45 cm]

    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, 2016
    2nd Thursday
    Bids + Registered Phone Bidders: 1
    Lot Tracking Activity: N/A
    Page Views: 904

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    25% on the first $200,000 (minimum $19), plus 20% of any amount between $200,000 and $2,000,000, plus 12% of any amount over $2,000,000 per lot.

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