Figure 1. This gold ring with a phoenix motif features a Neyshabur turquoise (13 × 17 mm), with a 0.02 ct ruby on each side and diamond accents. Courtesy of Taktala Jewelry, Tehran. Turquoise is an ...

Diamond is available in a range of sizes and qualities to fit every consumer's tastes. One of the first things most people learn about diamonds is that not all diamonds are created equal. In fact, ...

There is only one known commercial occurrence of gem-quality red beryl in the world: the Ruby Violet (or Red Beryl) mine in the Wah Wah Mountains of Beaver County, Utah. The beryl is found mostly ...

The Republic of Mozambique is located in southeastern Africa along the Indian Ocean. Separated from Madagascar by the Mozambique Channel, it is bordered by Tanzania to the north, South Africa to the ...

This note deals with some gemological applications for a tool well known to microscopists: the first-order red compensator. In gemological microscopy, the compensator can be useful in locating ...

Study Diamonds at GIA Through a unique combination of hands-on training, one-on-one coaching and multimedia, the Diamond Grading lab class explores how to grade diamonds consistently and accurately ...

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Both vibrational Raman and FTIR spectroscopy have been widely applied in identifying synthetic and natural beryl (Wood and Nassau, 1968; Schmetzer and Kiefert, 1990; Huong et al., 2010). These methods ...

这款 3.74 克拉 公主方形切工中等色调蓝色海蓝宝石由22 颗钻石环绕其周围。 这枚戒指是 Zoltan David（大卫·佐尔坦）的原创设计，已获得版权保护。 — Robert Weldon（罗伯特·韦尔登），由 Nancy's ...

Diamonds have a long history as a premier gemstone—a natural consequence of their beauty, rarity, and superlative physical properties such as extreme hardness. Diamonds that are mined for use as ...

Gem-quality synthetic or laboratory-grown diamonds are more available in today’s jewelry marketplace than ever before, causing both interest and concern about lab-grown diamonds and whether ...

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 ...