Grading

Star-Shaped Inclusions Spotted in Diamonds

GradingAug 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.

asteriated diamonds
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 … 

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. 

The Latest

Dua Lipa Bulgari Brand Ambassador
TrendsFeb 23, 2026
Dua Lipa Is Bulgari’s New Ambassador

Bulgari chose the British-Albanian singer-songwriter for her powerful and enduring voice in contemporary culture, the jeweler said.

US Supreme Court building
Policies & IssuesFeb 20, 2026
Supreme Court Rules Against Most of President Trump’s Tariffs

In a 6-3 ruling, the court said the president exceeded his authority when imposing sweeping tariffs under IEEPA.

Headshot of National Jeweler columnist Peter Smith
ColumnistsFeb 20, 2026
Peter Smith: Happiness, Cavemen, and Jewelry Sales

Smith encourages salespeople to ask customers questions that elicit the release of oxytocin, the brain’s “feel-good” chemical.

dca-laptop.jpg
Brought to you by
DCA Enters a New Chapter in Jewelry Education

With refreshed branding, a new website, updated courses, and a pathway for growth, DCA is dedicated to supporting retail staff development.

Jewelers Vigilance Committee logo
MajorsFeb 20, 2026
Jewelers Vigilance Committee Names Julie Yoakum Board Chair

JVC also announced the election of five new board members.

Weekly QuizFeb 19, 2026
This Week’s Quiz
Test your jewelry news knowledge by answering these questions.
Take the Quiz
Boucheron Faisceaux Brooch
CollectionsFeb 20, 2026
Boucheron’s ‘Faisceaux’ Brooch Heads to V&A Museum

The brooch, our Piece of the Week, shows the chromatic spectrum through a holographic coating on rock crystal.

Ann Weaver Bailey, also known as “Mama Ann”
IndependentsFeb 19, 2026
Bailey’s Fine Jewelry Co-Founder ‘Mama Ann’ Bailey Dies at 100

Raised in an orphanage, Bailey was 18 when she met her husband, Clyde. They opened their North Carolina jewelry store in 1948.

MJSA Apprenticeship Guide
Brought to you by
The MJSA Mentor & Apprenticeship Program: Attracting & Training the Next Generation of Bench Jewelers

Launched in 2023, the program will help the passing of knowledge between generations and alleviate the shortage of bench jewelers.

Material Good Boston Location Interior Rendering
IndependentsFeb 19, 2026
Material Good Opens Third Location

Material Good is celebrating its 10th anniversary as it opens its new store in the Back Bay neighborhood of Boston.

Original Miami Beach Antique Show sign
Events & AwardsFeb 19, 2026
The Original Miami Beach Antique Show Returns in March

The show will be held March 26-30 at the Miami Beach Convention Center.

Joanna Carson jewelry auction
AuctionsFeb 18, 2026
Joanna Carson’s Jewels Head to Auction

The estate of the model, philanthropist, and ex-wife of Johnny Carson has signed statement jewels up for sale at John Moran Auctioneers.

My Next Question podcast with Marion Fasel and Natalie Francisco
PodcastsFeb 18, 2026
Episode 2: Jewelry Trends & Does the Red Carpet Matter?

Are arm bands poised to make a comeback? Has red-carpet jewelry become boring? Find out on the second episode of the “My Next Question” podcast.

Select Jewelry Graziella Air
MajorsFeb 18, 2026
Select Jewelry Inks Agreement to Distribute Lightweight Gold Jewelry

It will lead distribution in North America for Graziella Braccialini's new gold pieces, which it said are 50 percent lighter.

Community for Ethical Jewelry Logo
Policies & IssuesFeb 18, 2026
Community for Ethical Jewelry Looks for Executive Director

The organization is seeking a new executive director to lead it into its next phase of strategic growth and industry influence.

DCA colored gemstone course on laptop
Events & AwardsFeb 18, 2026
DCA to Host Gemstone Selling Education Session at IJO Event

The nonprofit will present a live, two-hour introductory course on building confidence when selling colored gemstones.

Cece Jewellery Traveller’s Tale Ring
TrendsFeb 17, 2026
A Bit of Jewelry for the Year of the Horse

Western wear continues to trend in the Year of the Fire Horse and along with it, horse and horseshoe motifs in jewelry.

Anza gems
SourcingFeb 17, 2026
Colored Gemstone Experts Talk Tariffs, Trends in Tucson

Although the market is robust, tariffs and precious metal prices are impacting the industry, Stuart Robertson and Brecken Branstrator said.

Nest doorbell camera footage of suspect in Nancy Guthrie abduction
CrimeFeb 13, 2026
JSA Offering $10K Reward in Nancy Guthrie Case

Guthrie, the mother of “Today” show host Savannah Guthrie, was abducted just as the Tucson gem shows were starting.

Butterfield Jewelers going out of business sale ad
IndependentsFeb 13, 2026
97-Year-Old New Mexico Jewelry Store To Close

Butterfield Jewelers in Albuquerque, New Mexico, is preparing to close as members of the Butterfield family head into retirement.

Paul Morelli Rosebud Necklace
CollectionsFeb 13, 2026
A ‘Rosebud’ Necklace for Valentine’s Day

Paul Morelli’s “Rosebud” necklace, our Piece of the Week, uses 18-karat rose, green, and white gold to turn the symbol of love into jewelry.

Jewelers for Children
MajorsFeb 13, 2026
JFC Announces New Beneficiaries

The nonprofit has welcomed four new grantees for 2026.

Saks Fifth Avenue Club personal styling suite in Austin Texas
MajorsFeb 12, 2026
These 8 Saks Fifth Avenue Stores Are Closing

Parent company Saks Global is also closing nearly all Saks Off 5th locations, a Neiman Marcus store, and 14 personal styling suites.

Tudor Heart pendant on display at British Museum
CollectionsFeb 12, 2026
British Museum Raises $5M to Keep Jewel Linked to Henry VIII, Katherine of Aragon

It is believed the 24-karat heart-shaped enameled pendant was made for an event marking the betrothal of Princess Mary in 1518.

AGTA Spectrum, Cutting Edge Buyers Choice winners 2025
SourcingFeb 12, 2026
‘Cotton Candy’ Necklace, 35-Carat Kunzite Win 2025 ‘Buyer’s Choice’ Awards

The AGTA Spectrum and Cutting Edge “Buyer’s Choice” award winners were announced at the Spectrum Awards Gala last week.

Kering Logo
Events & AwardsFeb 12, 2026
Kering Opens Entries for 2026 Sustainability-Focused Award

The “Kering Generation Award x Jewelry” returns for its second year with “Second Chance, First Choice” as its theme.

Halle Berry’s vintage diamond and sapphire engagement ring
TrendsFeb 11, 2026
Halle Berry’s Retro Engagement Ring Is a Sapphire-Set Stunner

Sourced by For Future Reference Vintage, the yellow gold ring has a round center stone surrounded by step-cut sapphires.

Francesca’s storefront
MajorsFeb 11, 2026
Francesca’s Files for Chapter 11 Bankruptcy Again

The clothing and accessories chain announced last month it would be closing all of its stores.

×

This site uses cookies to give you the best online experience. By continuing to use & browse this site, we assume you agree to our Privacy Policy