An Interesting Rose Quartz from Madagascar

A new find of rose quartz from Madagascar contained some unusual inclusions.

続きを読む

Copper-Bearing (Paraíba-Type) Tourmaline from Mozambique

Copper-bearing tourmaline from Mozambique was first recovered in 2001, but its Cu content was not recognized until 2003, and it was not widely sold with its Mozambique origin disclosed until 2005.

続きを読む

A History of Diamond Treatments

Modern gemologists and diamantaires are faced with a broad spectrum of color and clarity treatments ranging from the simple to the highly sophisticated.

続きを読む

An Examination of the Napoleon Diamond Necklace

Napoléon Bonaparte gave an extraordinary diamond necklace to his empress, Marie-Louise, in 1811.

続きを読む

Identification of Melee-Size Synthetic Yellow Diamonds in Jewelry

Melee-size yellow synthetic diamonds have recently been seen in the gem market, mostly as loose stones but sometimes set in jewelry.

続きを読む

Apollo Diamond Inc. (アポロダイアモンド社)の最新世代のCVD(chemical vapor deposition 化学蒸着)成長合成ダイヤモンド (英語)

High-quality CVD-grown diamonds, comparable in color and clarity to natural diamonds, can be identified using a combination of gemological and spectroscopic properties.

続きを読む

Natural Type Ia Diamond with Green-Yellow Color Due to Ni-Related Defects

Commonly seen in HPHT-grown synthetic diamonds with a green component, nickel-related defects were identified for the first time in a type Ia natural diamond with a strong green component.

続きを読む

Continuity and Change in Chinese Freshwater Pearl Culture

Farmers have experimented with bead nucleation, but until recently the methods tried did not produce the quantity or quality necessary for economic success.

続きを読む

Global Rough Diamond Production Since 1870

Historically, global rough diamond production has fluctuated greatly due to a myriad of causes, many of which are explored in this article.

続きを読む

Fluorescence Spectra of Colored Diamonds Using a Rapid, Mobile Spectrometer

Numerous natural-color colored diamonds from the Aurora Butterfly of Peace and other collections were studied using a new type of fluorescence spectrometer.

続きを読む

The Impact of Internal Whitish And Reflective Graining on the Clarity Grading of D-To-Z Color Diamonds at the GIA Laboratory

This article reviews the GIA Laboratory’s history of reporting on certain types of graining which are often the only characteristics present in large, high-clarity, high-color diamonds.

続きを読む

Applications of Laser Ablation–Inductively Coupled Plasma–Mass Spectrometry (LA-ICP-MS) To Gemology

Laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) is an important technique for quantitative chemical analysis.

続きを読む

The Effects of Heat Treatment on Zircon Inclusions in Madagascar Sapphires

Zircon inclusions in sapphires from Madagascar were studied to investigate the effects of heat treatment on their gemological and spectroscopic features.

続きを読む

The Cullinan Diamond Centennial: A History and Gemological Analysis Of Cullinans I And II

Eight decades after the Cullinan diamond was mined, a team of gemologists examined the two famous gems that were created from it to become part of the Crown Jewels of England.

続きを読む

鉛ガラス充填ルビーの鑑別および耐久性 (英語)

In early 2004, the GAAJ laboratory in Japan issued a lab alert about rubies they had seen that had large numbers of fractures filled with high-lead-content glass, which made them appear very transparent.

続きを読む

Identification of “Chocolate Pearls” Treated by Ballerina Pearl Co.

Treated cultured pearls with a “chocolate” coloration have entered the market from several sources.

続きを読む

Inclusions in Transparent Gem Rhodonite from Broken Hill, New South Wales, Australia

Solid, vapor, and fluid inclusions in transparent gem rhodonite crystals from Broken Hill, New South Wales, Australia, have been identified for the first time using Raman spectroscopy and gemological/petrographic techniques.

続きを読む

A Review of the Political and Economic Forces Shaping Today’s Diamond Industry

Political upheavals and technological advances, as well as changes in social and governmental attitudes and initiatives, have produced major and ongoing changes in the diamond industry.

続きを読む

Mt. Mica: A Renaissance in Maine’s Gem Tourmaline Production

The Mt. Mica area in southwestern Maine has been mined for tourmaline and other pegmatite gems since the 1820s.

続きを読む

ザンビアのカフブ地方産のエメラルド (英語)

Zambia is considered the world’s second most important source of emeralds by value (after Colombia).

続きを読む

前へ100 / 149 ページ次へ

こちらもご覧ください

YMAL GIA Ed
通学やオンラインでの教育について学ぶ
Learn About NextGem
GIA ネクストジェム(NextGem) ダイヤモンド研修 小売業向け
Explore GIA Laboratory Promotional Offers
GIAラボラトリーの特別オファーを見る
Shop the GIA Store
GIAストアで ショッピング