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6.08 Carat Cobalt Blue Spinel from Tanzania - AIG Certified

$6,500
£4,900.58
€5,730.83
CA$9,200.12
A$10,302.30GST Included
CHF 5,393.58
MX$112,865.81
NOK 62,604.44
SEK 63,164.01
DKK 42,833.78

About the Item

This 6.08 carat cobalt-blue spinel displays the vivid, highly saturated blue colour that has made cobalt-bearing spinel one of the most sought-after gemstones among collectors and fine jewellery designers. Exhibiting a rich cobalt hue with lively internal brightness, the stone reveals flashes of blue under direct light while maintaining depth and saturation in softer illumination. Cut in a well-proportioned cushion shape measuring 10.73 × 9.94 × 6.36 mm, the gem presents a balanced outline and an impressive face-up presence for its carat weight. The brilliant crown and mixed pavilion faceting produce crisp scintillation and strong internal light return, allowing the colour to appear both vivid and luminous. The gemstone is reported as natural cobalt spinel from Tanzania and accompanied by a gemological report from AIG (American International GemLab) confirming no indications of heat treatment. Untreated cobalt-bearing spinel with strong saturation is uncommon, and examples exceeding five carats are rarely encountered on the market. Cobalt spinel from Tanzania—particularly stones displaying intense blue colour and good transparency—has become increasingly prized in recent years. Their distinctive colour results from trace amounts of cobalt within the spinel crystal structure, producing the striking neon-like blue that distinguishes this material from more typical blue spinels. With its combination of vivid colour, substantial size, and untreated status, this gemstone represents a compelling example of modern cobalt spinel and would be well suited for an important bespoke jewel or as a collector’s specimen. Stone Details Gemstone: Natural Spinel Variety: Cobalt-Bearing Blue Spinel Carat Weight: 6.08 carats Dimensions: 10.73 × 9.94 × 6.36 mm Shape: Cushion Cut Colour: Vivid Cobalt Blue - Medium Deep Tone Transparency: Transparent Treatment: No indications of heat Origin: Tanzania Laboratory Report: AIG – American International GemLab
  • Stone:
    Spinel
  • Stone Cut:
    Cushion Cut
  • Weight:
    6.08 ct
  • Dimensions:
    Height: 0.26 in (6.36 mm)Width: 0.4 in (9.94 mm)Length: 0.43 in (10.73 mm)
  • Place of Origin:
    Tanzania
  • Period:
    2010-
  • Date of Manufacture:
    2026
  • Condition:
  • Seller Location:
    Brisbane City, AU
  • Reference Number:
    Seller: CBS-TZ-0608-A1stDibs: LU4612228779942

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