Grading

GIA Finds Imitation Emerald Made of Layered Glass

GradingAug 23, 2018

GIA Finds Imitation Emerald Made of Layered Glass

The 3.35-carat stone had a natural beryl core; glass layers were attached to it with a “colorless cement.”

20180823_GIA-Header.jpg
A face-up view of the imitation emerald under cross-polarized light showing the inert reaction of the outer material and interference planes that outline the beryl core (Photomicrograph by Tyler Smith, GIA)

New York—Another gem has surfaced at a lab that was not entirely what it seemed.

A 3.35-carat “emerald” submitted to the Gemological Institute of America’s New York lab turned out to be an assembled imitation gemstone composed of five layers of glass cemented to a beryl core, according to an article by Tyler Smith and Augusto Castillo in the Summer 2018 issue of Gems & Gemology.

The rectangular core was a natural beryl, the mineral species to which emerald belongs, but the crown was a single piece of glass attached to the pavilion, while the pavilion was composed of four asymmetrical glass segments glued to the core using a “colorless cement.”

The imitation stone probably took a while to create using a “laborious multistep cut-and-glue process,” GIA authors said, as indicated by the way the four glass segments in the pavilion are interlocked.


When viewed face up, the imitation emerald showed the natural inclusions seen underneath the table as well as large bubbles visible at the corners of the beryl core. (Photo by Jian Xin (Jae) Liao, GIA)
The manufacturing of the piece started by attaching a glass segment to the beryl core. Both were then cut to create a flat surface for a second piece of glass. The second was then added, cut to allow for the third, and so forth.

After all four had been added, the assembled pavilion likely would have been polished flat to allow for the crown, which then would have been attached.

(Check out the original lab note from GIA for a diagram showing the process.)

The article also noted that while assemblages of various materials have long been used to imitate precious stones—with the most common kind using two or more pieces joined together in parallel, layered fashions—GIA researchers weren’t able to find record of another stone assembled using the process applied to this “emerald.”

RELATED CONTENT: Glued-Together Diamond Turns Up at GIA
GIA said it was the first time one such assembled stone has been submitted to its New York or Carlsbad laboratories.

Researchers surmise that the imitation emerald was created relatively recently, given the fact that all its exposed surfaces are made of glass and, yet, the facet junctions are still sharp and the stone lacks wear.

“It is intriguing that an antiquated technique is updated in modern times, serving as a cautionary tale of the ingenuity counterfeiters employ,” the authors said.
Brecken Branstratoris the senior editor, gemstones at National Jeweler, covering sourcing, pricing and other developments in the colored stone sector.

The Latest

Melanie Georgacopoulos Eclipse Collection Campaign Imagery
CollectionsMay 04, 2026
Melanie Georgacopoulos Turns Pearls Into Light for ‘Eclipse’ Collection

The “Eclipse” jewelry collection captures the fleeting moment where light and shadow align though onyx, diamonds, and freshwater pearls.

National Jeweler columnist Sherry Smith, partner at The Retail Smiths
ColumnistsMay 04, 2026
The Key Mindset for Better Trade Show Buying

Buying discipline at trade shows starts with clarity about your inventory levels, Smith writes.

Mugshot of 20-year-old Landen Julian Ballard of Vero Beach, Florida
CrimeMay 04, 2026
Pawn Shop Manager Shot, Killed in Florida

Lazaro Rodriguez Vega was murdered inside Cash Out Gold and Silver in Fort Pierce. A 20-year-old man has been charged in the case.

Antique Jewelry & Watch Show
Brought to you by
Discover Timeless Treasures: A Showcase of Antique Jewelry & Timepieces in Las Vegas

Gain access to the most exclusive and coveted antique pieces from trusted dealers during Las Vegas Jewelry Week.

Gild Zadok, Segev Zadok, and Jonathan Zadok at Austin park
IndependentsMay 04, 2026
Zadok Jewelers, Austin Parks Foundation Support Wildflower Preservation

A portion of every engagement ring sold in its Austin showroom will support the care and preservation of Austin’s wildflowers and green spaces.

Weekly QuizApr 30, 2026
This Week’s Quiz
Test your jewelry news knowledge by answering these questions.
Take the Quiz
Gemist new retailer offering
TechnologyMay 01, 2026
Gemist, Saban Onyx Partner on Retailer-Focused Customization Offering

Their partnership combines Gemist’s customization technology with Saban Onyx’s U.S.-based manufacturing capabilities.

Hand putting gas pump in car
SurveysMay 01, 2026
Consumer Confidence Inches Up in April Despite Rising Gas Prices

Respondents were concerned about the Middle East conflict and how it will impact their finances.

lvajws image 1.jpg
Brought to you by
Las Vegas Antique Jewelry & Watch Show: Showcasing the Most Collectible Merchandise from Across the Globe

Gain access to the most exclusive and coveted antique pieces from trusted dealers during Las Vegas Jewelry Week.

Tiffany & Co. Blue Book 2026: Hidden Garden Butterfly Diamond Necklace
CollectionsMay 01, 2026
A ‘Hidden Garden’ Emerges in Tiffany & Co.’s 2026 Blue Book

Our Piece of the Week, the “Butterfly” necklace, showcases a 7.02-carat oval diamond set between diamond, platinum, and 18-karat gold wings.

The Retail Smiths partner and National Jeweler columnist Peter Smith
ColumnistsApr 30, 2026
Peter Smith: A Sleazy Salesman and the Case for Regret Avoidance

Smith uses a comment he overheard in the grocery store to remind retailers that their job is to inspire buying behavior, not just sell.

Claire’s new summer campaign
MajorsApr 30, 2026
Claire’s New Summer Campaign Is a Sensory Wonderland for Gen Alpha

“A Girl SMR at Claire’s” celebrates girlhood through the five senses with stacked jewelry, slime toys, scented accessories, and ASMR.

Cartier London Crash Watch
AuctionsApr 30, 2026
Vintage Cartier Watch Crashes Through Records, Selling for $2M

Believed to be one of three made in 1987, the Cartier London Crash was hot at the “Shapes of Cartier” sale at Sotheby’s Hong Kong.

Police cars
CrimeApr 30, 2026
Masked Group Uses Hammers, Pepper Spray in Texas Jewelry Store Robbery

Officials are looking for a group that robbed Marc Robinson Jewelers at an outlet mall in Round Rock, Texas, in broad daylight on April 21.

OAR26_NJ_bulletin_1872x1052_01.jpg
Supplier BulletinApr 30, 2026
OROAREZZO 2026: The B2B Event for Italian Excellence in Goldsmith, Jewelry and Silver Manufacturing

Sponsored by OROAREZZO International Jewelry Exhibition

Tiffany & Co. Mother’s Day email opt out
TechnologyApr 29, 2026
The Thought Process Behind the Mother's Day Email Opt-Out

Some retailers are taking a nuanced approach to marketing what can be a difficult holiday for many.

Dick Abbott
IndependentsApr 29, 2026
Dick Abbott to Retire From The Edge

The Edge has announced its new CEO, as well as a new partnership with an investment firm focused on founder-led software businesses.

The Venetia Diamond Mine in South Africa
SourcingApr 29, 2026
De Beers’ Production Rises, Market Remains ‘Challenged’

De Beers’ diamond production was up 17 percent in Q1, boosted by increased output at its mines in South Africa and Canada.

John Wayne Signet Ring
AuctionsApr 29, 2026
This'll Be the Day You Own John Wayne's Ring

A signet ring belonging to the Western film star of Hollywood’s Golden Age will be up for auction at Elmwood’s next month.

Stock image of money
Policies & IssuesApr 28, 2026
Tariff Refunds: How to File, What to Expect

Importers can submit claims now to receive money back for the IEEPA tariffs they’ve paid, with refunds expected to take up to 90 days.

Gregory's Jewelers storefront
IndependentsApr 28, 2026
This North Carolina Jeweler Is Passing the Torch

The owners of Gregory Jewelers in Morganton, North Carolina, are heading into retirement.

Doug Hucker
SourcingApr 28, 2026
Doug Hucker Retires From ICA

The colored gemstone industry leader is heading into retirement after four years as the association’s CEO.

Natural Diamond Council Chief Marketing Officer Susie Dewey
SourcingApr 28, 2026
NDC Hires Tapestry Exec to Head Global Marketing

Susie Dewey joins the Natural Diamond Council as its new chief marketing officer.

The Ocean Dream diamond
AuctionsApr 27, 2026
12 Years Later, the ‘Ocean Dream’ Diamond Resurfaces at Christie’s

The largest known fancy vivid blue-green diamond could fetch more than $12 million at its second auction appearance.

Smart Age Solutions CEO and National Jeweler columnist Emmanuel Raheb
ColumnistsApr 27, 2026
Stop Treating Mother’s Day Like an Afterthought

Emmanuel Raheb says jewelers need to start marketing early and make it easy for customers to pick a gift for mom.

Longnecker Jewelry storefront
IndependentsApr 27, 2026
Longnecker Jewelry Celebrates 30 Years

In honor of the milestone, the Nebraska jeweler has debuted Leslie & Co., its new in-house jewelry brand.

Jeff Corey
MajorsApr 27, 2026
JBT Re-Elects Jeff Corey as Board Chair

The trade organization, which held its annual elections earlier this year, also added five new board members.

Fourteen August Irene mom ring
SurveysApr 24, 2026
Mother’s Day 2026 Jewelry Spending to Top $7B, NRF Says

NRF’s annual survey found that 45 percent of consumers plan to purchase jewelry for a loved one this Mother’s Day.

×

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