MajorsMay 17, 2021
Pandora’s Head of North America Steps DownGradingMay 26, 2021
Stuller Hires Guy Borenstein as Senior Gemologist
He has relocated from Israel to Louisiana to lead its gemological laboratory.
Industry veteran Guy Borenstein has been named senior gemologist at Stuller, leading the supplier’s gem lab.
Lafayette, La.—Industry veteran Guy Borenstein has joined Stuller’s team.
The supplier named him senior gemologist; he will be the lead gemological authority for the company.
Borenstein succeeds Mike Turner in the role, who passed away suddenly in December 2019.
He and his family have relocated from Israel to Lafayette, Louisiana, where Stuller is headquartered.
He started working there in early May, the company confirmed, where he leads the gemological laboratory, which sits alongside its in-house GIA Melee Analysis service lab and its team of diamond and gemstone experts.
Its lab contains advanced gemological equipment that allows them to screen for and detect undisclosed lab-grown diamonds.
Related stories will be right here …
The supplier named him senior gemologist; he will be the lead gemological authority for the company.
Borenstein succeeds Mike Turner in the role, who passed away suddenly in December 2019.
He and his family have relocated from Israel to Lafayette, Louisiana, where Stuller is headquartered.
He started working there in early May, the company confirmed, where he leads the gemological laboratory, which sits alongside its in-house GIA Melee Analysis service lab and its team of diamond and gemstone experts.
Its lab contains advanced gemological equipment that allows them to screen for and detect undisclosed lab-grown diamonds.
Borenstein’s role at Stuller will help the company comply with RJC Code of Practices and FTC rules regarding product integrity, a spokesperson for the company confirmed.
He joined Stuller with 15 years of experience in various gemological disciplines, including serving as the vice president of gemological services at Gemewizard and chief gemologist at EGC and GWLAB laboratories.
He is a Gemmological Association of Great Britain FGA and holds an EGG (E.G.L. Graduate Gemologist) diploma from the European Gemological College.
“Guy is a world-class talent, highly respected among leading gemologists, and we are fortunate to have him join the Stuller team,” said Stanley Zale, vice president of diamond and gemstone procurement at Stuller.
“He is a great addition to our team. His knowledge and skills will help us continue to lead the industry with robust programs that best ensure the integrity of our products.”
He joined Stuller with 15 years of experience in various gemological disciplines, including serving as the vice president of gemological services at Gemewizard and chief gemologist at EGC and GWLAB laboratories.
He is a Gemmological Association of Great Britain FGA and holds an EGG (E.G.L. Graduate Gemologist) diploma from the European Gemological College.
“Guy is a world-class talent, highly respected among leading gemologists, and we are fortunate to have him join the Stuller team,” said Stanley Zale, vice president of diamond and gemstone procurement at Stuller.
“He is a great addition to our team. His knowledge and skills will help us continue to lead the industry with robust programs that best ensure the integrity of our products.”
More on Grading
The Latest
Policies & IssuesNov 14, 2025
U.S., Switzerland Reach Deal That Drops Tariff to 15%The Swiss government announced the deal, which cuts the tax on Swiss imports by more than half, on social media Friday morning.
AuctionsNov 14, 2025
Napoleon’s Diamond Brooch Blows Away Auction Estimates A buyer paid $4.4 million for the piece, which Napoleon wore on his hat for special occasions and left behind when he fled Waterloo.
FinancialsNov 14, 2025
Richemont’s Q2 Jewelry Sales Up 12%Plus, how tariffs and the rising price of gold are affecting its watch and jewelry brands.
Brought to you by
Roseco Releases New Full-Line CatalogRoseco’s 704-page catalog showcases new lab-grown diamonds, findings, tools & more—available in print or interactive digital editions.
CollectionsNov 14, 2025
Piece of the Week: Silvia Furmanovich’s ‘Butterflies in Flight’ Jewelry BoxFurmanovich designed the box to hold Mellerio’s “Color Queen,” a high jewelry collection consisting of 10 rings.
Weekly QuizNov 13, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
Events & AwardsNov 14, 2025
JCK Names New Event DirectorJennifer Hopf, who has been with JCK since 2022, will lead the execution of the long-running jewelry trade show.
IndependentsNov 13, 2025
127-Year-Old New Orleans Jeweler to CloseAdler’s Jewelry is set to close its two stores as 82-year-old owner Coleman E. Adler II retires.
Brought to you by
Jewelers of America Aligns New Mission to Create Meaningful Impact for MembersFrom educational programs, advocacy, and recent MJSA affiliation, Jewelers of America drives progress that elevates businesses of all sizes.
IndependentsNov 13, 2025
Green Lake Jewelry Works to Move to New Seattle StudioFounder Jim Tuttle shared how a dedication to craftsmanship and meaningful custom jewelry fueled the retailer’s double-digit growth.
MajorsNov 13, 2025
Vahan Jewelry Founder Leon ‘Sacha’ Der Calousdian Dies at 85The third-generation jeweler is remembered as a passionate creative with a love of art, traveling and sailboat racing.
CrimeNov 12, 2025
Father, Son Jewelers in Chicago Victims in Double Homicide JSA and Cook County Crime Stoppers are both offering rewards for information leading to the arrest of the suspect or suspects involved.
AuctionsNov 12, 2025
‘Mellon Blue’ Diamond Sells for $7M Less Than It Did a Decade AgoA buyer paid $25.6 million for the diamond at Christie’s on Tuesday. In 2014, Sotheby’s sold the same stone for $32.6 million.
AuctionsNov 12, 2025
Historic Rolex Oyster Fetches $1.7M at Sotheby’sMercedes Gleitze famously wore the watch in her 1927 swim across the English Channel, a pivotal credibility moment for the watchmaker.
MajorsNov 10, 2025
Jewelers Focus on Love, Joy In 2025 Holiday Campaigns Tiffany & Co., David Yurman, and Pandora have launched holiday campaigns depicting their jewelry as symbols of affection and happiness.
SurveysNov 10, 2025
5 Things Retailers Should Know About Holiday Shoppers This YearThe National Retail Federation is bullish on the holidays, forecasting retail sales to exceed $1 trillion this year.
AuctionsNov 10, 2025
300+ Colored Diamonds Up for Auction at Christie’sLate collector Eddy Elzas assembled “The Rainbow Collection,” which is offered as a single lot and estimated to fetch up to $3 million.
EditorsNov 07, 2025
Piece of the Week: An MVP’s Sapphire Tennis Necklace At the 2025 World Series, the Los Angeles Dodgers’ Yoshinobu Yamamoto sported a custom necklace made by California retailer Happy Jewelers.
IndependentsNov 07, 2025
Foundrae’s New Palm Beach Location Is a ‘Golden Solarium’The brand’s seventh location combines Foundrae’s symbolic vocabulary with motifs from Florida’s natural surroundings.
FinancialsNov 07, 2025
Watches of Switzerland’s H1 Sales Up 8%The retailer also shared an update on the impact of tariffs on watch customers.
SourcingNov 06, 2025
Pink Tourmaline Bracelet, Emerald Suite Take Top Spectrum Honors Pink and purple stones were popular in the AGTA’s design competition this year, as were cameos and ocean themes.
IndependentsNov 06, 2025
Greenwich St. Jewelers Hosts Raffle Supporting Food RescueAll proceeds from the G. St x Jewel Boxing raffle will go to City Harvest, which works to end hunger in New York City.
IndependentsNov 06, 2025
Cornell’s Jewelers Names New PresidentCourtney Cornell is part of the third generation to lead the Rochester, New York-based jeweler.
SourcingNov 06, 2025
De Beers’ Production, Sales Increase in Q3 De Beers also announced more changes in its upper ranks ahead of parent company Anglo American’s pending sale of the company.
WatchesNov 05, 2025
Shinola President Steps Down Just as He Starts Former Signet CEO Mark Light will remain president of Shinola until a replacement for Ulrich Wohn is found.
AuctionsNov 05, 2025
Taylor Swift’s Engagement Ring Designer Makes Her Auction DebutKindred Lubeck of Artifex has three rings she designed with Anup Jogani in Sotheby’s upcoming Gem Drop sale.
FinancialsNov 05, 2025
Pandora Posts Modest Q3 Sales Growth Amid ‘Weak’ Consumer Sentiment The company focused on marketing in the third quarter and introduced two new charm collections, “Pandora Talisman” and “Pandora Minis.”
FinancialsNov 05, 2025
Brilliant Earth’s Q3 Sales Climb 10%The jewelry retailer raised its full-year guidance, with CFO Jeff Kuo describing the company as “very well positioned” for the holidays.
