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UNMOUNTED COLOUR-CHANGE COBALT SPINEL image 1
UNMOUNTED COLOUR-CHANGE COBALT SPINEL image 2
Lot 541

UNMOUNTED COLOUR-CHANGE COBALT SPINEL

5 – 12 August 2025, 12:00 HKT
Online, Hong Kong

Sold for HK$16,640 inc. premium

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UNMOUNTED COLOUR-CHANGE COBALT SPINEL

3.15克拉天然「坦桑尼亞」未經處理變色鈷藍色尖晶石
Certificate: Bellerophon, cobalt spinel, natural, 3.159ct, colour change: blue to violet, Mahenge (Tanzania), untreated
(B30603, 17 September 2024)

Footnotes

NO RESERVE 不設底價

CONDITION REPORT:
Violetish blue under natural light. Prominent colour-change effect from blue to violet to direct incandescent and yellow light. Good brilliance. Medium-strong tone and medium saturation. To 10x magnification there is a crystal inclusion near one of the corner.

This condition report is provided for your convenience based on the opinion of our specialists. Bonhams is not responsible for any discrepancies between this information and other opinions. The condition of lots can vary widely and the nature of the lots sold means that they are unlikely to be in perfect condition. The dimensions and weights of diamonds and gemstones are approximated using measurements and given as a courtesy, please consider them as an estimation only.

Please note additional images and videos are available upon request, kindly contact the jewellery department at jewellery.hk@bonhams.com

Additional information

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