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 ...

This 7.19-carat alexandrite was cut to feature its beautiful color change. When the light source changes from daylight to incandescent light, the gem’s color changes from bluish green to reddish ...

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, ...

In 1983, the Argyle mine was established as the first major diamond-mining operation in Australia. Almost immediately, it became the world’s largest source of diamonds in terms of the volume (carats) ...

Soon after it was first marketed in 1976, colorless cubic zirconia became the dominant diamond imitation, with current production of approximately 60 million carats per year. Although cubic zirconia ...

This sapphire from Kashmir has an intense velvety blue color. – Photo: Robert Weldon/GIA. Sapphire is one of the Big three of jewelry colored gemstones—the other two are ruby and emerald. A durable ...

Microscopic mineral inclusions are responsible for the gem's mysterious haziness. This lovely pastel gem often has internal fractures that give it a cloudy translucence, so it’s generally cut into ...

This ancient necklace dates to 2000BCE. An inscription on the center stone is a South Arabian script from the 8th century BCE. - From "Gems and Gemstones: Timeless Natural Beauty of the Mineral World" ...

Those born in January are lucky to have the beautiful and diverse garnet as their birthstone. Garnets are commonly red but also come in an extraordinary range of beautiful colors, including orange, ...

需小心护理以避免损坏。月光石是拥有近乎神奇光泽的珠宝。 - Richard Krementz Gemstones 友情提供 硬度和韧度 莫氏硬度用以衡量宝石和矿物的硬度。 这些数字基于一种矿物可被其他物品划伤的相对难易程度得出。 但莫氏硬度容易产生误导。 矿物之间的等级差距 ...

To open a new GIA Laboratory Service Account or to keep your existing account current, you’ll need to provide a signed, up-to-date GIA Laboratory Client Agreement. A signed agreement is required ...