Gem News International Gems & Gemology, Spring 2025, Vol. 61, No. 1 Green Jadeite-Omphacite from Guatemala. Jennifer Stone-Sundberg, Aaron Palke, and Wim Vertriest ...

GIA CAMPUSES ARE WORLDWIDE. With schools in major gem and jewelry centers around the world, GIA campuses are exciting learning environments. From the bustle of Mumbai’s diamond trading center to the ...

GIA scholarship application cycle is from April 15 to May 15, 2023. To apply, click the button below to learn more. GIA-administered scholarships are available for GIA campuses worldwide. • Applicants ...

According to Hole et al. (1969), the earliest Persian turquoise artifacts were discovered in the Deh Luran Plain in western Iran. Radiocarbon dating suggests that turquoise beads found in burial sites ...

In November 2022, a parcel of 24 approximately 0.5–1.2 ct spinel crystals, described as cobalt-diffused, were obtained directly from a treater by the research team at GIA in Bangkok. Of these, seven ...

As shown in figure 2, diamonds have formed over a wide range of the earth’s geologic history. The oldest dated examples are diamonds with an age of 3.5–3.3 Ga (billion years) from the Diavik and Ekati ...

Laboratory-Grown Diamonds. Man-made diamonds suitable for industrial use were first produced in a laboratory in the 1950s. While gem-quality diamonds were produced in a laboratory for the first time ...

Figure 3. Formation of the pink-brown eclogitic diamonds at Argyle—the world’s largest diamond deposit. After their formation, Argyle pink-brown diamonds resided in the high-temperature, ...

These diamonds are from the 2016 Argyle Pink Tender in New York City. Left to right: 0.64 ct Fancy Deep pink oval, 0.75 ct Fancy Intense purplish pink trilliant, 0.91 ct Fancy Vivid purplish pink oval ...

Recently, the author analyzed an interesting 41.51 ct faceted bicolor beryl (figure 1) composed of aquamarine and opaque white beryl. This gem belongs to Brazilian gem dealer Veber Leite and is part ...

GEOLOGICAL SETTING. The island of Phu Quoc lies in the Gulf of Thailand, about 45 km off the southwestern coast of Vietnam. The island has an area of 574 km 2.The terrain consists mainly of low ...

Mozambican rubies have revolutionized the dynamics of the ruby trade since their debut on the global gem scene in 2009. GIA has been following the evolution of the deposits around Montepuez in the ...