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Figure 1. A fine 925 ct crystal that was formerly displayed in the Texas State Capitol and sat on the governor’s desk in 1969 when the legislature adopted blue Texas topaz as the state gem. This specimen was found in 1904 and now resides in the Hamman Gem and Mineral Gallery in the Department of Earth and Planetary Sciences at the University of Texas at Austin (catalog no. B0344). Photo by Blanca Espinoza.

Topaz from Mason County, Texas

Roy Bassoo, Diane Eames, Matthew F. Hardman, Kenneth Befus, and Ziyin Sun, January 26, 2024

A comprehensive look at Texas topaz, detailing its gemological and compositional characteristics and providing a basis for using trace element concentrations to identify its origin.

A greenish blue octahedral crystal of gahnospinel found in Sri Lankan blue sapphire. Photomicrograph by Yusuke Takamura; field of view 3.81 mm.

Octahedral Gahnospinel Crystal in Sri Lankan Blue Sapphire

Yusuke Takamura, January 26, 2024

A rare octahedral gahnospinel crystal is observed in Sri Lankan sapphire.

Article

Winter 2023 G&G Available Now

Erica Zaidman, January 26, 2024

An overview of the Winter 2023 Gems & Gemology content.

Texas Topaz, Slovak Opal, a Beryl Inclusions Chart, and More

Duncan Pay, January 26, 2024

An overview of the Winter 2023 Gems & Gemology content.

Article

Fall 2023 G&G Available Now

Erica Zaidman, November 3, 2023

An overview of the Fall 2023 Gems & Gemology content.

Cause of Color in Yellow Sapphire, Plus Characterization of Oregon Sunstone, Ukrainian Beryl, and British Columbian Iolite

Duncan Pay, November 3, 2023

An overview of the Fall 2023 Gems & Gemology content.

Figure 1. From left: Jacob Lowry, Sean Hyrons, Matthew Wernz, and Kenneth Van Wey engage in a panel discussion titled “Laws: Liabilities and Protections.” Photo courtesy of the Turquoise Museum.

Turquoise United Conference 2023

Alex Goodsuhm and Aaron Palke, November 3, 2023

A recap of the second annual Turquoise United Conference.

The rectilinear zigzag-patterned fingerprint in this 3.21 ct blue sapphire shows beautiful vibrant colors, indicating a Sri Lankan origin. Photomicrograph by Yuxiao Li; field of view 4.45 mm.

Zigzag Fingerprint in Sri Lankan Sapphire

Yuxiao Li, November 3, 2023

Fiber-optic illumination reveals rectilinear zigzag-patterned films with vibrant colors in a blue sapphire.

Figure 2. Rectangular step-cut green beryl from the Volyn pegmatite, 190.00 ct and 28.55 × 39.02 × 21.71 mm, with a rough unpolished table containing etch pits. Faceting and photo by Konstantyn Zalizko.

Etch Pits in Heliodor and Green Beryl from the Volyn Pegmatites, Northwest Ukraine: A Diagnostic Feature

Gerhard Franz, Oleksii A. Vyshnevskyi, Volodymyr M. Khomenko, Peter Lyckberg, and Ulrich Gernert, November 3, 2023

Examines dissolution features of heliodor and green beryl from a Ukrainian pegmatite field and offers criteria to distinguish them from samples found in other localities.

Figure 12. Rough and cut iolite from Blue Bear. From left to right, the faceted stones weigh 1.24, 0.48, 0.48, and 0.88 ct. Photo by Philippe Belley.

Iolite from the Thor-Odin Dome, British Columbia, Canada: Geology, Chemical Composition, Inclusions, and Cause of Chatoyancy

Philippe M. Belley, November 3, 2023

Reports on the geological setting and gemological properties of violet-blue gem cordierite from new deposits located in British Columbia.

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