Lot 3028
Rare and Exceptional Grandidierite and Diamond Ring
16 June 2021, 10:00 PDT
Los AngelesSold for US$75,312.50 inc. premium
Looking for a similar item?
Our Lapidary Works of Art specialists can help you find a similar item at an auction or via a private sale.
Find your local specialistAsk about this lot
Client Services (Los Angeles)
Client Services (New York)
Rare and Exceptional Grandidierite and Diamond Ring
Madagascar
Grandidierite is a rare mineral that was first discovered in 1902 in southern Madagascar. The mineral was named in honor of French explorer Alfred Grandidier (1836–1912) who studied the natural history of Madagascar and wrote a 40 volume treatise entitled, L'Histoire physique, naturelle et politique de Madagascar.
With a relative Mohs hardness of 7.5, Grandidierite is ideally suited for mounting as jewelry--when it can be discovered--yet most crystals found are dull and opaque with a pearly luster.
The present offering is an absolutely unique gemstone of nearly 7 carats: faceted as a cushion-shape brilliant-cut having a remarkable transparency and a lovely bluish green color. It is set in a European hand-made platinum ring decorated with 377 fine quality near-colorless diamonds, weighing altogether 3.89 carats. Such a stone is a unique opportunity for the serious collector of gemological rarities and one which is unlikely to occur again. Weighing approximately 6.95 carats and measuring 12.95 x 12.04 x 5.84mm, size 6 1/2.
Grandidierite is a rare mineral that was first discovered in 1902 in southern Madagascar. The mineral was named in honor of French explorer Alfred Grandidier (1836–1912) who studied the natural history of Madagascar and wrote a 40 volume treatise entitled, L'Histoire physique, naturelle et politique de Madagascar.
With a relative Mohs hardness of 7.5, Grandidierite is ideally suited for mounting as jewelry--when it can be discovered--yet most crystals found are dull and opaque with a pearly luster.
The present offering is an absolutely unique gemstone of nearly 7 carats: faceted as a cushion-shape brilliant-cut having a remarkable transparency and a lovely bluish green color. It is set in a European hand-made platinum ring decorated with 377 fine quality near-colorless diamonds, weighing altogether 3.89 carats. Such a stone is a unique opportunity for the serious collector of gemological rarities and one which is unlikely to occur again. Weighing approximately 6.95 carats and measuring 12.95 x 12.04 x 5.84mm, size 6 1/2.
Footnotes
Accompanied by an SSEF (Schweizerisches Gemmologisches Institut) Report # 106703 stating that the Grandidierite exhibits a remarkable size and weight and is characterized by an attractive blue green color and fine purity, a combination rarely encountered in Grandidierite of this size. SSEF additionally adds that Grandidierite of gem quality is very rare and only a few stones have been cut so far, commonly of very small size, thus, a natural Grandidierite of this size can be considered rare and exceptional.
Accompanied by a Gemological Institute of America report numbered 7306565917 dated September 12, 2018 identifying the gemstone and an additional notable letter stating:
"This Grandidierite exhibits a bluish green coloration, characteristic of this magnesium-aluminum borosilicate mineral. Microscopy revealed a limited number of inclusions such as needles and naturally healed fractures. The high clarity and appealing color also combine to enhance the stone's unique character.
Grandidierite is known as a rather rare mineral from a few localities including: Sri Lanka, Italy, New Zealand and Madagascar. Typically, faceted stones are small in size only reaching a few carats. Stones of any size are highly sought after by rare gemstone collectors due to the mineral's rarity. The rarity of grandidierite makes this a notable gemstone.
Accompanied by a GRS (Gemresearch Swisslab) gemstone report numbered GRS2018-117050 dated November 14, 2018 stating that the 6.95 carats cushion-shaped stone of bluish green shows no indication of thermal treatment and that it originates from Madagascar and that it has a rare combination of size, fine color and good transparency.
