Below is the list of recognized holidays when GIA locations will be closed.View the holiday schedule for all GIA locations worldwide.

Figure 1. Sapphires from Madagascar: a beautiful 3.29 ct untreated faceted stone and an assortment of rough in the background. Madagascar has produced many high-quality stones in the last few years ...

Northern Mozambique (figure 1) has gained attention for its rubies since a major discovery near Montepuez in 2009 (see McClure and Koivula, 2009; Pardieu and Lomthong, 2009; Pardieu and Chauvire, 2012 ...

The sparks will fly − and your diamond will shine − when you follow these cleaning tips. Diamond is the hardest natural substance on Earth. It can cut any kind of rock or metal, but only another ...

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 ...

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 ...

The Karowe Diamond Mine in Botswana, owned and operated by Lucara Diamond Corp., has gained international recognition for producing large, high-quality type IaB or coexistence of IaB with IIa diamonds ...

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 ...

GIA’s Diamond Cut Grading system for round brilliant diamonds includes seven components: brightness, fire, scintillation, weight ratio, durability, polish and symmetry. Fire is well illustrated in ...

This raspberry-and mint-colored tourmaline—nicknamed the “Steamboat”—is one of the world’s finest and most valuable mineral specimens. Photo by Duncan Pay ...

Once upon a time, gem cutting was a strict craft bound by centuries of tradition. The job of a lapidary was to cut a gemstone to ideal proportions while preserving as many carats as possible. Then ...

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 ...