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
CrimeDec 11, 2024
Former Tiffany & Co. Factory Supervisor Sentenced for Stealing Precious Metals A federal judge gave Benjamin Preacher 59 days in jail, plus 10 months of home confinement and two years of supervised release.
IndependentsDec 10, 2024
Sauer Opens First U.S. StoreThe Brazilian jewelry brand made a home on New York City’s Madison Avenue with exclusive pieces only available at the location.
SurveysDec 10, 2024
Jewelry Among Top Sellers on Cyber Monday, Says AdobeAn Adobe Analytics report explored the rise in mobile shopping, the popularity of Buy Now Pay Later options, and peak shopping hours.
Brought to you by
Advocacy and Excellence: How Jewelers of America Is Committed to Elevating Our Industry For over a century, Jewelers of America has been the voice of the industry and valuable resource to jewelers across the country.
Events & AwardsDec 10, 2024
AGTA Launches Scholarship for University of Arizona Geosciences StudentsThe inaugural Dick Greenwood Memorial Scholarship in Gems Science will cover the fall 2025 and spring 2026 semesters.
Weekly QuizDec 05, 2024
This Week’s QuizTest your jewelry news knowledge by answering these questions.
Events & AwardsDec 10, 2024
JA New York To Debut 2 New Pavilions at Spring 2025 ShowA Piazza Italia pavilion will feature Italian designers and manufacturers while “MJSA Showcase” brings over a piece of the MJSA Expo.
CollectionsDec 09, 2024
Ray Griffiths’ First Coffee Table Book Spans 5 Decades of Design“Ray Griffiths: The Works” tells the story of the master jeweler’s career, which started with an apprenticeship in Australia at age 15.
Brought to you by
Protecting Your Sparkle: Why Screening Has Become Essential While no reputable jeweler would knowingly sell lab-grown stones as natural, it's a growing possibility.
MajorsDec 09, 2024
Thomas Davis, Grant Mobley Join WJA Foundation Board Davis is the director of business development at Select Jewelry Inc., and Mobley is the jewelry and watch editor at the Natural Diamond Council.
FinancialsDec 09, 2024
Movado’s Q3 Sales Down 3% Amid ‘Challenging’ EnvironmentThe retailer has been upping its marketing spend to drive revenue growth and brand awareness.
IndependentsDec 06, 2024
After 44 Years in Business, This Wisconsin Independent Is ClosingMike Straub and John Treiber opened Treiber & Straub in 1980 with the goal of bringing Milwaukeeans the best jewelry brands.
TrendsDec 06, 2024
Pantone’s Color of the Year Is a Delicious MousseThe color for 2025, “Mocha Mousse,” embodies thoughtful indulgences and everyday pleasures.
CollectionsDec 06, 2024
Piece of the Week: Cocoerow Fine Jewelry’s ‘Kokoro’ PendantThe Yoruba word for ant, “Kokoro” embodies the strength of womanhood in ant society while highlighting responsible sourcing.
FinancialsDec 06, 2024
Roberto Coin Acquisition Gives Watches of Switzerland a Boost in H1The retailer’s jewelry sales doubled, with branded jewelry performing especially well.
FinancialsDec 05, 2024
Signet Jewelers’ Q3 Sales Slide Amid Slow Engagement Ring Sales, Tech IssuesThe jewelry retailer addressed the lab-grown diamond “disruption,” the price of gold, and its holiday weekend performance.
SurveysDec 05, 2024
Consumer Confidence Rises Again in NovemberA more positive view of the current labor market boosted the Conference Board’s index last month.
Events & AwardsDec 05, 2024
Michael S. Krzemnicki to Receive 2024 Bonanno AwardThe director of the Swiss Gemmological Institute (SSEF) will be honored for his impact on gemology and dedication to advancing the science.
Supplier BulletinDec 05, 2024
Join Us For Color's Premier Show: 2025 AGTA GemFair TucsonSponsored by 2025 AGTA GemFair Tucson
Events & AwardsDec 05, 2024
BIJC Announces 2024 ‘Rock the Jewels’ Awards WinnersAt the annual event, in its second year, the organization honored those making remarkable contributions to the jewelry industry.
TrendsDec 05, 2024
Amanda’s Style File: A Blue, Blue, Blue Month Celebrate December babies with 20 pieces of jewelry featuring this month’s birthstones—turquoise, tanzanite, and zircon.
SurveysDec 04, 2024
In-Store Shopping Outpaced Online Over the Holiday Weekend, Says NRF A total of 126 million consumers shopped in stores over the five-day period, about 5 million more than last year.
Lab-GrownDec 04, 2024
GJEPC Says Indian Trade Will Use FTC-Approved Terminology for Lab-Grown DiamondsThe FTC’s Jewelry Guides require “clear and conspicuous” disclosure when advertising lab-grown diamonds.
SourcingDec 04, 2024
Designer Saul Fraiman Retires After 55 YearsThe fine jewelry designer, who came out of retirement in 2017, is putting down his sketchpad for good.
AuctionsDec 04, 2024
30-Carat Pink Diamond Fetches $2.6M at BonhamsThe Type IIa, very light pink colored diamond was the highlight of the recent Hong Kong jewelry auction.
CrimeDec 03, 2024
Man Sentenced to Life in Prison for Murder of Florida JewelerJohn Willard Craiger, 83, fatally shot jeweler Ghazi “Gus” Michel Osta following an argument in the store.
ColumnistsDec 03, 2024
Peter Smith: How a Leadership Hire Can Make or Break a CompanyIn his latest column, Smith provides a list of questions every business needs to be asking their next potential leader.
SourcingDec 03, 2024
Gemstone Cutter Glenn Lehrer Dies at 71An innovative artist inspired by the natural world, Lehrer is remembered for being a visionary and a shining light.
