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 ...

Large quantities of rubies—both rough and faceted—from a commercially important new source in Myanmar (Burma) have been available on the Bangkok market since 1992. The ruby crystals from the Mong Hsu ...

Observations of Oval-, Pear-, and Marquise-Shaped Diamonds: Implications for Fancy Cut Grading Presents findings from observations of oval-, pear-, and marquise-shaped diamonds, laying the groundwork ...

The September birthstone is sapphire – a gem that’s been cherished for thousands of years. Although the term sapphire usually refers to the blue variety of corundum (ruby is the red variety), this ...

Although various forms of paints and coatings intended to alter the color of diamond have likely been in use for almost as long as diamonds have been valued as gems, the modern era of diamond ...

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" ...

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.

GIA IT will be performing maintenance on our internal systems from Friday, October 18th (5 PM PT) to Saturday, October 19th 2024 (8 PM PT). During this maintenance window, the My Lab application, ...

The GIA Laboratory-Grown Diamond Report includes full quality assessment with a plotted clarity diagram. Color and clarity specification are described on the same scale as the GIA Diamond Grading ...

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 ...

Twenty-six peridot samples from the Esquel pallasite meteorite and 27 samples from 10 terrestrial sources were studied by laser ablation–inductively coupled plasma–mass spectrometry (LAICP- MS). Among ...

With proper care, lapis lazuli can provide a lifetime of jewelry-wearing enjoyment. - Dr. Edward J. Gübelin Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the ...