Ruby is the July birthstone – and it’s one of the most coveted of gems. The name is derived from the Latin word ruber, meaning “red” – the color of love and passion. Few things catch the eye like the ...

Emeralds are formed when chromium, vanadium, and iron are present in the mineral beryl. The varying presence of these three elements gives emerald its range of color. Chromium and vanadium make an ...

A hand-held flashlight reveals the green color of a rough emerald from the Coscuez Emerald mine in Colombia. Photo by Eric Welch/GIA. Emerald is the green to bluish green variety of beryl, a mineral ...

This amethyst crystal is from Namibia. It shows classic quartz crystal shape: a six-sided columnar crystal with a pyramid-shaped termination at the top. Courtesy Daniel Trinchillo, Fine Minerals ...

Reviews the advancements and major trends in laboratory-grown diamonds observed by GIA since 2007. Gemological and Trace Element Characteristics of Cassiterite from Yunling, China Examines gem-quality ...

The 75.47-carat Hooker Emerald was worn by Ottoman Sultan Abdul Hamid II, the last sultan of the Ottoman Empire. Photo by Chip Clark, courtesy Smithsonian Institution, National Museum of Natural ...

This 146.10-carat peridot is in the collection of the Natural History Museum in London Peridot has always been associated with light. In fact, the Egyptians called it the “gem of the sun.” Some ...

Pearl’s Mohs hardness is 2.5, so care should be taken not to scratch it. Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with which one ...

This large Australian light opal cabochon weighs 117.85 carats. Small play-of-color flashes of orange and green predominate in a pinfire pattern, with spots of a more muted blue over a grayish ...

Useful contact information if you’re looking for a professional to value your gem or jewelry item. GIA does not provide an appraised value for gemstones or jewelry. This service should be performed by ...

This 10.12 ct Fancy Vivid yellow pear shape illustrates the effect a fancy shape can have on intensifying the color in a yellow diamond. - Courtesy the Scarselli Family Color In diamonds, rarity ...

As a consumer, you will regularly encounter in the marketplace gems that have been treated to change their appearance. A topic that often comes up is whether a particular gemstone is or isn’t treated.