SurveysSep 15, 2025
Resilient Shoppers to Boost Holiday Retail Sales, Says DeloitteIt’s predicting a rise in retail sales this holiday season despite economic uncertainty and elevated inflation.
EditorsApr 08, 2019
5 Things to Know About … Grandidierite
Learn where and when the gemstone was discovered, its current supply outlook and where you can go to see a few today.
A rough grandidierite crystal rests next to a beautiful 9.3-carat faceted grandidierite from Brice Gobin of Mineral Art. (Photo credit: Jeff Scovil)
When I was in Tucson, the team at Omi Gems’ booth treated me to something special: a viewing of not one but six grandidierite gems.
I had heard of the gemstone before but had never seen one in person. As it turns out, not many people have. They’re rare, and let me tell you, they’re gorgeous.
Grandidierite is bluish-green to greenish-blue, with the blue component increasing with the iron content, according to the GIA.
It’s a 7.5 on the Mohs scale, making it suitable for use in jewelry (when available), but according to the International Gem Society, it is difficult to cut because it has good cleavage in two directions.
It also displays trichroic pleochroism, meaning it can show three different colors depending on the angle at which it’s viewed: dark blue-green, pale yellow or colorless, or dark green.
In honor of the stone I was excited to see and learn about in Tucson, here are five things to know about grandidierite.
1. It was first discovered in Madagascar.
French mineralogist Alfred Lacroix found the first reported samples of grandidierite in 1902.
He discovered the gemstone at the cliffs of Andrahomana in southern Madagascar, according to the GIA.
2. It was named for someone.
As is the case with a few other minerals ending in “ite,” grandidierite was named after a person.
Lacroix christened the mineral “grandidierite” in honor of another Alfred: French explorer and naturalist Alfred Grandidier (1836-1912), who was the first explorer to describe Madagascar in detail, according to the Cambridge History of Africa.
He devoted his life to gathering information for his massive “Histoire physique, naturelle et politique de Madagascar,” which was 38 volumes long.
I had heard of the gemstone before but had never seen one in person. As it turns out, not many people have. They’re rare, and let me tell you, they’re gorgeous.
Grandidierite is bluish-green to greenish-blue, with the blue component increasing with the iron content, according to the GIA.
It’s a 7.5 on the Mohs scale, making it suitable for use in jewelry (when available), but according to the International Gem Society, it is difficult to cut because it has good cleavage in two directions.
It also displays trichroic pleochroism, meaning it can show three different colors depending on the angle at which it’s viewed: dark blue-green, pale yellow or colorless, or dark green.
In honor of the stone I was excited to see and learn about in Tucson, here are five things to know about grandidierite.
1. It was first discovered in Madagascar.
French mineralogist Alfred Lacroix found the first reported samples of grandidierite in 1902.
He discovered the gemstone at the cliffs of Andrahomana in southern Madagascar, according to the GIA.
2. It was named for someone.
As is the case with a few other minerals ending in “ite,” grandidierite was named after a person.
Lacroix christened the mineral “grandidierite” in honor of another Alfred: French explorer and naturalist Alfred Grandidier (1836-1912), who was the first explorer to describe Madagascar in detail, according to the Cambridge History of Africa.
He devoted his life to gathering information for his massive “Histoire physique, naturelle et politique de Madagascar,” which was 38 volumes long.
A 1.43-carat emerald-cut grandidierite from Omi Gems
3. It has since been found elsewhere.
In addition to Madagascar, GIA said other reported sources of the mineral include New Zealand, Norway, Suriname, Algeria, Italy, Malawi, India, the United States, Canada, Antarctica and the Czech Republic.
Since its discovery more than a century ago, very little gem-quality grandidierite has surfaced and most of what has been found is translucent.
However, a 2014 discovery of more transparent material outside of Tarnomaro, Madagascar, near the site where the first pieces of grandidierite were found, has resulted in several fine quality faceted stones, according to the Gemmological Association of Great Britain’s Gems & Jewellery spring issue.
4. It is extremely rare.
Despite the number of sources, grandidierite is still extremely rare; pockets tend to be small and quickly become depleted.
Much of the material that comes out of the ground is opaque, IGS said. As mentioned before, even when gem-quality material is produced, it’s often translucent (semi-transparent), and is thereby cut into cabochons ranging in size from about 1 carat to 10 carats and up.
According to GIA’s Gems & Gemology, gem-quality grandidierite of “facetable size” was “almost unheard of” in the market before the summer of 2015.
Bangkok-based gemstone dealer MultiColour Gems said on its website that the ratio of gem-quality crystals to rough is about 1 in 10,000.
The company noted that the Tranomaro deposit, where the 2014 discovery occurred, has produced only about 60 grams (300 carats) of eye-clean crystals.
Given its rarity, fine grandidierite gems can demand significant prices.
For example, gem dealer and Mineral Art manager Brice Gobin is quoted in the Gems & Jewellery article as saying that a buyer paid $50,000 in 2003 for the first known transparent faceted grandidierite, which weighed only 0.29 carats, a fact confirmed by GIA.
These three grandidierite gemstones are on display at the Wilensky Gallery in New York right now. They weigh (from left) 3.14 carats, 4.96 carats and 2.86 carats.
Even so, minimal supply goes hand-in-hand with low demand and a lack of knowledge about the stone among many jewelers, according to Gobin.
“Grandidierite is too rare to be able to provide the jewelry market,” he is quoted as saying. “No supply, no demand; it’s as simple as that.”
5. You can see grandidierite gems in New York right now.
For those who haven’t seen grandidierite in person or are looking for the perfect collector gemstone, one Manhattan gallery provides the perfect opportunity.
Gobin sourced a collection of grandidierite gems from the Tranomaro region of Madagascar over an 18-month period, Gems & Jewellery reported. The selection included some 20 gems weighing between 1 and 9-plus carats.
Three of Gobin’s grandidierite gemstones will be on display at the Wilensky Gallery in New York City through at least June, representing the gallery’s foray into faceted gemstones.
They weigh 2.86, 3.14 and 4.96 carats and are priced at $69,000, $78,000 and $129,500, respectively.
I was lucky enough to get to see those, too, during a recent WJA event at the gallery, and I’m telling you: Run, don’t walk, to see these gems before they’re gone.
More on Editors
The Latest
SourcingSep 15, 2025
Gemfields Achieves $32M at High-Quality Emerald AuctionIt included the sale of the 11,685-carat “Imboo” emerald that was recently discovered at Kagem.
SourcingSep 15, 2025
AGTA Elects 8 Members to Board of Directors The newly elected directors will officially take office in February 2026 and will be introduced at the organization’s membership meeting.
Brought to you by
reDollar.com Is Rolling Out the Next Level Jewelry, Diamond & Watch Consignment ProgramWith their unmatched services and low fees, reDollar.com is challenging some big names in the online consignment world.
TrendsSep 12, 2025
Piece of the Week: Arunashi’s Fordite and Rhodolite EarringsFordite is a man-made material created from the layers of dried enamel paint that dripped onto the floors of automotive factories.
Weekly QuizSep 12, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
Events & AwardsSep 12, 2025
Al Gilbertson Wins 2025 Robert M. Shipley AwardGilbertson has worked as a researcher, jeweler, lapidary artist, appraiser, and business owner throughout his decades in the industry.
Policies & IssuesSep 11, 2025
Supreme Court to Hear Tariffs Case in November A decision likely won’t come until January 2026 at the earliest, and the tariffs remain in effect until then.
Brought to you by
Rallying Call for the Jewelry Industry on Tariffs and Other Key IssuesJewelers of America is leading the charge to protect the industry amidst rising economic threats.
MajorsSep 11, 2025
Tabayer Opens Nordstrom Shop-In-ShopLocated in the revamped jewelry hall at the retailer’s New York City flagship, this opening is Tabayer’s first shop-in-shop.
SourcingSep 11, 2025
Need to Sell More Natural Diamonds? De Beers Has an App for ThatThe new, free app offers accessible educational content, like games and podcasts, for U.S. retailers.
MajorsSep 10, 2025
Stuller to Swap Gold Scrap for Full Credit to AccountAs the gold price rises, the manufacturer is offering a 100 percent payout through Sept. 30 for gold clean scrap.
SourcingSep 10, 2025
Tech Meets Style in the New Loewe x Jacob & Co. HeadphonesJacob & Co. partnered with the German technology company on two pairs of headphones, one set with diamonds and the other with sapphires.
TrendsSep 10, 2025
Tiffany & Co. Archival Jewels Bring Life to ‘Frankenstein’Guillermo del Toro’s 2025 “Frankenstein” will feature 27 jewels and objects from the storied brand, including pieces from its archives.
MajorsSep 10, 2025
24 Karat Club of New York’s Banquet to Return to Waldorf AstoriaThe Waldorf Astoria New York’s grand reopening this past summer means a homecoming for the industry group’s annual event.
SourcingSep 09, 2025
Anglo American to Merge With Canadian Copper Miner Anglo plans to merge with Teck Resources Ltd. to form Anglo Teck. The deal changes nothing about its plans to offload De Beers.
AuctionsSep 09, 2025
‘The Mellon Blue’ to Return to Auction, This Time at Christie’s The 9.51-carat fancy vivid blue diamond, which set two world auction records at Sotheby’s in 2014, is estimated to fetch up to $30 million.
AuctionsSep 09, 2025
Phillips Names Dianne Batista Head of Jewels, New YorkThe industry veteran joins the auction house as it looks to solidify its footprint in the jewelry market.
MajorsSep 09, 2025
MJSA Education Foundation Announces 2025 Scholarship WinnersThe nonprofit awarded four students pursuing a professional career in jewelry making and design with $2,250 each.
IndependentsSep 08, 2025
Take a Look Inside the New Korman Store in AustinThe Texas-based jeweler has also undergone a brand refresh, debuting a new website and logo.
MajorsSep 08, 2025
MJSA Is Officially Now Under JA’s UmbrellaThe two organizations have finalized and signed the affiliation agreement announced in May.
AuctionsSep 08, 2025
Sotheby’s To Auction ‘Exceptional’ Collection of JAR, Suzanne Belperron JewelsThe single-owner sale will headline Sotheby's inaugural jewelry auction at the Breuer building, its new global headquarters, this December.
Events & AwardsSep 08, 2025
27 Can’t-Miss Converge Sessions, Events From sunrise yoga to tariffs talks, these are some events to check out at the upcoming inaugural event.
ColumnistsSep 05, 2025
Peter Smith: A Lasting Lesson From Maurice Tempelsman Smith recalls a bit of wisdom the industry leader, who died last week, shared at a diamond conference years ago.
CollectionsSep 05, 2025
Piece of the Week: Jamie Turner’s ‘Victoria’ Necklace The “Victoria” necklace features a labradorite hugged by diamond accents in 18-karat yellow gold.
Policies & IssuesSep 05, 2025
Trump Takes Tariffs Case to the Supreme Court Two lower courts have moved to block the import taxes, which will remain in place as the legal battle continues.
WatchesSep 05, 2025
Patrick Mahomes Is the New Hublot Brand AmbassadorThe Kansas City Chiefs quarterback shares Hublot’s dedication to pursuing greatness, the Swiss watchmaker said.
