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61.65CTS BI-VALVE OPALISED FOSSIL FO-1852 fossi lopals

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1 watching
Details
SKU
fo-1852
Dimensions (mm)
35.2 x 21.4 x 16.7mm
Weight (cts)
61.65
Colours
Description

PARENT COMPANIES: TRUE BLUE OPALS PTY LTD & LIGHTNING OPALS LLC

BI-VALVE

COOBER PEDY, SOUTH AUSTRALIA

OPALISED FOSSIL

GOOD COLOR

Bivalve fossils from Coober Pedy are famous opalized marine clams, typically from the Lower Cretaceous period (around 100 million years old), found in the Bulldog Shale where silica replaced the shell material, creating stunning iridescent specimens often polished to reveal vibrant colors, with common types like Cyrenopsis. These unique fossils showcase ancient marine life preserved within the precious opal for which Coober Pedy is renowned, sometimes including other creatures like belemnites or marine reptiles.

Key Characteristics:

  • Opalization: The shells' original calcium carbonate was replaced by opal (hydrous silica), preserving intricate details and color.

  • Age: Lower Cretaceous, part of the Eromanga Sea environment that covered ancient Australia.

  • Types: Often identified as Cyrenopsis australiensis, a type of clam.

  • Appearance: Polished specimens display a range of colors (fire) due to light interference within the opal's microstructure.

  • Rarity: Opalized fossils are rare, making them prized collectibles.

Where They're Found:

  • Coober Pedy Opal Field, South Australia: The primary location for these fossils.

  • Bulldog Shale: The geological layer where they are unearthed.

Significance:

  • They provide a unique glimpse into ancient marine ecosystems from Australia's dinosaur age, as fossils from this period are generally scarce.

  • They are highly valued by collectors and gem enthusiasts for their beauty and rarity.


Shipping
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61.65CTS BI-VALVE OPALISED FOSSIL FO-1852 fossi lopals
Qld, Australia
Owned by fossil opals
Recent Feedback
  • ntasky87
    ntasky87
    Positive

    Love this little fossil! The colours really pop and is so much better in person!! Thank you.

  • bagheera
    bagheera
    Positive

    Gorgeous piece quick delivery

Audit

The Opal Sheriff program allows our members to request an audit on any product, which is completed by an independent Gemologist who assesses the accuracy of the item description and pictures.

Shipping Details

Costs:
Transit:
14 days via Standard Shipping - Tracked
Ships from:
Australia

Payment Options

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Overview

Listing Type : Premium
Product ID : 1668287
Starts : 19th December 2025 03:50 am PST
* All prices are in USD

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