Ruby and Diamond Ring | 天然「坦桑尼亞」未經加熱紅寶石 配 鑽石 戒指（紅寶石重約10.01克拉）
Auction Closed
July 19, 10:42 AM GMT
Estimate
2,000,000 - 3,200,000 HKD
Lot Details
Description
Set with a cushion-shaped ruby weighing approximately 10.01 carats, decorated with baguette and brilliant-cut diamonds, mounted in 18 karat white gold, size 5¾.
Accompanied by Gübelin report, appendix and information sheet no. 22040102, dated 5 May 2022, stating that the ruby is of Tanzanian origin, with no indications of heating. Gübelin appendix further stating that 'The natural ruby described ... is ...from Winza. It has a saturated and homogeneous colour, combined with a high degree of transparency... has been spared thermal treatment. Such a combination of characteristics is rare in natural rubies of this size.'
Also accompanied by SSEF report no. 122193, dated 25 April 2022, stating that the ruby is of Winza, Tanzanian origin, with no indications of heating.
Rubies from Tanzania were first discovered in the early 20th century near Longido, in the northern part of the country. During the 1960s more corundum deposits were found near the Kenyan border in the Umba river valley. Historically these sources were known to originate mostly cabochon-quality pieces, with only a few exceptional quality stones. Therefore, when high-quality rubies were found in Winza in the late 2000s from both eluvial and primary deposits, it was welcomed by the market as a pleasant surprise. The location is close to the capital city of Dodoma and next to Mahenge, which produces the famous Mahenge spinels with a vibrant pinkish-red colour to the market. Being close to the Mozambique belt that produces high-quality rubies, with the best of Winza rubies characterized by exceptional colour and size, Tanzania has become a new source for fine rubies. This ring is accompanied by a Gubelin appendix explaining Tanzanian rubies, stating that the ruby graded has a ‘saturated and homogenous color, combined with a high degree of transparency…such as combination of characteristics is rare in natural rubies of this size.’