
Natural Opal with Unusual Play-of-Color Pattern
Play-of-color pattern in Ethiopian opal is reminiscent of a turtle’s shell.

Cristobalite Stars and Snowflakes in Devitrified Glass
A unique inclusion scene caused by devitrification is observed in artificial glass.

Trapiche Pattern Formation of Grossular Garnets
GIA’s Tokyo laboratory examines three grossular garnets displaying six-rayed black inclusions arranged in a snowflake-like pattern.

Pink Diamond with Mottled Appearance
Examination of a Fancy Deep brownish orangy pink diamond reveals evidence of treatment to enhance its color.

Extraordinary Large Bicolor Natural Rough Diamond
A 37.41 ct natural rough diamond with distinct pink and colorless zones is examined at GIA’s Botswana laboratory.


Palaeoclavaria burmitis Inclusions in Burmese Amber
Fungal inclusions are studied in two specimens of Burmese amber.

Raw Brilliance: Nature’s Diamond Sculptures
Showcases the diverse natural shapes of rough diamonds and explores how geological processes create their unique forms.

Characterization of “Orange Peel” Surface Microstructure of White Nephrite from Russia: A Unique Pseudomorph Pattern
Examines correlations between surface microstructures and the orange peel effect in Russian white nephrite, proposing a formation model and revealing distinctive microfeatures specific to the material.

A Guide to Diamonds with the 480 nm Absorption Band
Summarizes the features of 480 nm band diamonds, including chameleon diamonds and those with unmodified orange hues, for rapid identification or advanced gemological testing.

External Morphology and Internal Zonal Structure of Macle Diamond
Investigates the morphological changes of macle diamonds during the growth process by exploring their three-dimensional internal zonal structure.

Gaseous Carbon Dioxide Phases in Paraíba Tourmaline
Immiscible two-phase fluid inclusions are investigated in a 0.48 ct Paraíba tourmaline.
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GIA 授予蘇珊·雅克傑出成就獎
During the GIA Board of Governors meeting in early November at the Institute’s headquarters in Carlsbad, CA, the Institute honored Susan M. Jacques with its highest honor, the Richard T. Liddicoat Award for Distinguished Achievement.
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GIA、Susan Jacques氏を表彰
11月初旬、カリフォルニア州カールスバッドにあるGIA本部で開催された理事会において、同機関はSusan M. Jacques氏に対し、最高栄誉であるRichard T. Liddicoat功績賞で表彰しました。

Extraordinary Large Bicolor Natural Rough Diamond
A 37.41 ct natural rough diamond with distinct pink and colorless zones is examined at GIA’s Botswana laboratory.

How GIA Analyzes Pearls from Start to Finish

Amit Pratihari 獲任命為 GIA India Laboratory Pvt. Ltd.董事總經理
The board of directors of GIA India Laboratory Pvt. Ltd. (GIA India) has appointed Amit Pratihari as managing director, responsible for all aspects of GIA India’s gemological laboratories in Mumbai and Surat, as well as the GIA India school in Mumbai.

Amit Pratihari Named Managing Director, GIA India Laboratory Pvt. Ltd.
The board of directors of GIA India Laboratory Pvt. Ltd. (GIA India) has appointed Amit Pratihari as managing director, responsible for all aspects of GIA India’s gemological laboratories in Mumbai and Surat, as well as the GIA India school in Mumbai.


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