Describes the geology, mineralogy, and formation of granitic-composition pegmatites and provides a summary of their worldwide occurrences. Structures Behind the Spectacle: A Review of Optical Effects ...

GIA offers many opportunities for students to receive a scholarship. Scholarship offerings are made available to assist eligible students in reducing their financial burden and focusing on completing ...

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 ...

Tutti Frutti (bold color contrasts using carved gemstones) dazzles in this bracelet, brooch, and lapel watch by Mauboussin. Jewelry courtesy of Kathryn Bonanno. The Roaring Twenties – It’s a time that ...

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 ...

Sri Lanka’s gemstone and jewelry industry blends traditional practices and experience with the needs of the modern global market. Photo by Andrew Lucas/GIA. To visit Sri Lanka is to experience one of ...

Figure 1. The vivid colors seen in fine gem-quality spinel are derived from the mixing between multiple different chromophores in a range of ratios and concentrations, as in this fine 13.52 ct ...

Raman spectroscopy confirmed the identity of the material as pezzottaite by an intense peak at ~1100 cm –1, which is not present in beryl. Fourier-transform infrared spectroscopy showed features ...

Figure 1. A view of the Lombok farm from the shoreline showing the covered area where the operating and harvesting steps are carried out. Photo by Jeffery Bergman. Cultured pearls are harvested from ...

Two specimens of faceted crystalized carbon - both are crystal clear and give off a kaleidoscope of spectral colors in direct light. They appear to be identical. One, however, is a billion or more ...

The earliest GIA course materials in the Richard T. Liddicoat Gemological Library and Information Center that mention the 4Cs are from 1949. Going back as far as the 1500s, merchants used many ...

Figure 1. Glass in a silver brooch, hallmark from 1866. Private collection, photo by Jaroslav Hyršl. Tectites are members of a large group of impact glasses, formed by the collision of a meteorite on ...