Blue diffusion-treated sapphires are becoming more prevalent than ever before. The diffusion technique, which involves the addition of color-causing chemicals during heat treatment, results in a thin ...

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 ...

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

Ruby crystals from Southeast Asia with a fixed six-rayed star, similar in effect to trapiche emeralds from Colombia, are described. They consist of six transparent-to-translucent ruby sectors ...

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 ...

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. 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 ...

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 ...

Carbon is one of the most important elements on our planet, which led the Geological Society of London to name 2019 the Year of Carbon. Diamonds are a main host for carbon in the deep earth and also ...

Ask anyone what the most important characteristic of their diamond is and they’re likely to say it’s the “Wow” factor. You want your friends and family to stop, stare and admire the stone dancing on ...