GradingJul 30, 2024
Gübelin Academy Bringing Colored Gemstone Course to NYCGradingAug 13, 2024
Star-Shaped Inclusions Spotted in Diamonds
GIA recently examined two asteriated diamonds, weighing about 8 carats each, that it said were notable for their large size and preserved natural forms.
The asteriated diamonds displayed light brown cloud inclusions shaped like stars.
Carlsbad, Calif.—Two natural diamonds with star-shaped inclusions were recently submitted to the Gemological Institute of America’s Carlsbad laboratory for examination.
The asteriated or “star” diamonds, weighing 8.14 carats and 8.57 carats, appeared in the lab’s summer 2024 edition of “Gems & Gemology.”
The stones displayed light brown cloud inclusions, which come from high concentrations of hydrogen and nickel during their growth period, said GIA, and may also contain graphite.
GIA said asteriated diamonds are occasionally submitted to the lab, but these two stones are notable for their large size and preserved natural forms.
The 8.14-carat diamond was resorbed—partially dissolved by natural fluid or magma, causing it to take on a rounded shape—and maintained most of its rough form on one side.
The stone was sliced to show the underlying inclusion pattern on the other side.
The preserved rough surfaces also displayed brown radiation stains, which are an indication that it had natural alpha irradiation followed by annealing in the earth.
The 8.57-carat diamond was polished with bruted edges.
Related stories will be right here …
The asteriated or “star” diamonds, weighing 8.14 carats and 8.57 carats, appeared in the lab’s summer 2024 edition of “Gems & Gemology.”
The stones displayed light brown cloud inclusions, which come from high concentrations of hydrogen and nickel during their growth period, said GIA, and may also contain graphite.
GIA said asteriated diamonds are occasionally submitted to the lab, but these two stones are notable for their large size and preserved natural forms.
The 8.14-carat diamond was resorbed—partially dissolved by natural fluid or magma, causing it to take on a rounded shape—and maintained most of its rough form on one side.
The stone was sliced to show the underlying inclusion pattern on the other side.
The preserved rough surfaces also displayed brown radiation stains, which are an indication that it had natural alpha irradiation followed by annealing in the earth.
The 8.57-carat diamond was polished with bruted edges.
Both diamonds’ clouds fluoresced green when subjected to long-wave UV, which GIA said is consistent with previously studied asteriated diamonds.
Also, both stones showed high concentrations of hydrogen, which the lab detected using bulk Fourier-transform infrared spectroscopy.
Using photoluminescence mapping for the 8.14-carat stone, the lab saw that several nickel-related defects were detected inside the cloud inclusion sector but not outside of it.
GIA also analyzed the diamonds using X-ray computed microtomography, which allowed the asteriated growth sectors to be viewed in 3-D reconstructions.
It found the asteriated regions more strongly absorb X-rays than the rest of the diamond.
This indicates, the lab said, the combined signal from the diamond and inclusions likely had a higher atomic number.
More on Grading
The Latest
Events & AwardsJun 06, 2025
Here Are the 2025 Retailer Hall of Fame InducteesThis year’s honorees include a Midwest retailer and two multi-store independents, one in New York and the other in New England.
CollectionsJun 06, 2025
Piece of the Week: Harwell Godfrey’s ‘Granny Squares Eleanor’ Necklace As an homage to iconic crochet blankets, the necklace features the nostalgic motif through a kaleidoscope of cabochon-cut stones.
Events & AwardsJun 05, 2025
The 12 Fresh Faces in Couture’s Design AtelierDiscover the dozen up-and-coming brands exhibiting in the Design Atelier for the first time.
Brought to you by
The True Power Behind the Counter: Why Sales Associates Are the Heart of the Jewelry BusinessWhen investing in your jewelry business, it's important not to overlook the most crucial element of success: the sales associates.
SourcingJun 05, 2025
A Rare Suite of Rubies Has Arrived in Las VegasThe “Royal Ruby” Collection is a quintet of untreated rubies curated by collector Jack Abraham.
Weekly QuizJun 05, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
Events & AwardsJun 05, 2025
Daymond John to Give Keynote at JCK Las VegasThe entrepreneur and “Shark Tank” star will share his top tips for success.
MajorsJun 05, 2025
Platinum Guild International Updates Leadership TeamTwo existing executives have been given new roles.
Brought to you by
Clienteling Isn’t a Buzzword. It’s an Essential Business Model.More shoppers are walking out without buying. Here’s how smart jewelers can bring them back—and the tool they need to do it right.
Events & AwardsJun 05, 2025
Zillion Announces 'Women in STEM' Scholarship RecipientMeredith Tiderington, an electrical engineering student, was selected for the award.
Lab-GrownJun 04, 2025
GIA Reverting to More General Terminology for Lab-Grown DiamondsIt will quit assigning the stones specific color and clarity grades in favor of applying “new descriptive terminology.”
Events & AwardsJun 04, 2025
As JCK Talks Returns, Don’t Miss These 12 SessionsFrom design trends to sustainability, here’s a roundup of can’t-miss education sessions at JCK Las Vegas.
CrimeJun 04, 2025
10 Safety Tips for the Las Vegas Shows The Jewelers’ Security Alliance offers advice for those attending the annual trade shows.
MajorsJun 04, 2025
Amy Curran Promoted at Hill & Co.Her new role is director of strategic initiatives.
CollectionsJun 03, 2025
In Her Latest Collection, Viviana Langhoff Is Leaning Into GoldThe designer is embracing bold pieces with weight to them in “AU79,” a collection she celebrated with a creative launch party.
FinancialsJun 03, 2025
Signet Jewelers Sees Turnaround in Q1 With Sales Ticking Up 2%On an earnings call, CEO J.K. Symancyk discussed what’s working for the company and how it’s preparing for the potential impact of tariffs.
SurveysJun 03, 2025
Consumer Confidence Improves in May The index partially rebounded after months of decline, due in part to the U.S.-China deal to temporarily reduce import tariffs.
CollectionsJun 03, 2025
Dakota Johnson Is Roberto Coin’s New Brand AmbassadorThe actress stars in the latest campaign set in Venice, Italy, and is set to participate in other creative initiatives for the jeweler.
SourcingJun 02, 2025
Gemfields’ June Auction to Include 36-Carat RubyThe large stone will be offered at its June sale along with a selection of secondary-type rubies from a new area of the Montepuez mine.
TrendsJun 02, 2025
Amanda’s Style File: Three Gems for June Those born in June have a myriad of options for their birthstone jewelry.
SourcingJun 02, 2025
David Allouche Joins Grandview Klein DiamondsThe diamond industry veteran has been named its senior sales executive.
FinancialsMay 30, 2025
Movado’s Q1 Sales Slip Amid ‘Challenging’ Retail Environment The company plans to raise the prices of select watches to offset the impact of tariffs.
Policies & IssuesMay 30, 2025
Tariffs & Designers: Navigating Pricing in an Unstable EnvironmentBetween tariffs and the sky-high cost of gold, designers enter this year’s Las Vegas shows with a lot of questions and few answers.
CollectionsMay 30, 2025
Piece of the Week: Renato Cipullo’s ‘Hematite Blaze’ NecklaceDesigned by founder Renato and his daughter Serena Cipullo, it showcases a flame motif representing unity and the power of gathering.
Policies & IssuesMay 30, 2025
Trade Court Declares Trump’s Tariffs InvalidHowever, the tariffs remain in effect in the short term, as an appeals court has stayed the U.S. Court of International Trade’s decision.
CollectionsMay 29, 2025
Britney Spears Files Trademark for New Jewelry LineThe pop icon is one step closer to launching her “B Tiny” jewelry collection, a collection she first began posting about last fall.
Supplier BulletinMay 29, 2025
Inoveo Platinum Grain, Exclusively Distributed by StullerSponsored by Stuller
SourcingMay 29, 2025
Grizzly Auctions 6,620-Carat EmeraldIt was featured in the miner’s latest sale, which brought in $24.8 million.
