Of all the sapphire deposits found in Montana, the richest is in the Rock Creek (Gem Mountain) district. Between 1890 and the 1930s, over 65 tonnes of rough sapphire were recovered from this area and ...

While the public is generally unaware of Mozambique as a ruby source, the deposit near Montepuez is considered by the trade to be the world’s largest supplier. Gemfields’ first Mozambique ruby auction ...

Since its discovery at the beginning of the nineteenth century, infrared light has proven to be a versatile tool for scientists, industrialists, and consumers. The gem industry has benefited from the ...

Once a stone is submitted, client information is withheld from the non-client-facing staff who conduct the analysis. This measure helps ensure an unbiased report. Before undergoing examination, each ...

Sri Lanka has two monsoon seasons that occur at different times of the year depending on the part of the country. The northeast has monsoons from December through March. In the southwest, where most ...

Earth’s surface is divided into tectonic plates, and the ones that make up the ocean floor are destined to sink. Sheets of oceanic crust typically bend and sink down into Earth’s interior at so-called ...

The Imperial Flame, a superb natural color Brazilian topaz, was fashioned from a 615 ct crystal recovered over 20 years ago. The finished piece measures 89.53 × 20.56 × 19.15 mm and weighs 332.24 ct.

Rough pink diamonds are rarely found, and although the cause of color has been correlated with plastic deformation, the precise mechanism and atomic configuration for the resulting color are topics of ...

A half century ago, Akwatia was one of the most productive diamond spots on the planet. Diamonds were discovered at the nearby Birim River in 1920, when the nation was a British colony called the Gold ...

Collectors from around the world descended on Christie's Maharajas & Mughal Magnificence auction of jewels from the Al-Thani Collection on June 19. By the time the New York sale ended, they had spent ...

GIA has named John Cowley, a seasoned executive with more than 30 years of global financial and operational experience, as the Institute’s next chief financial officer (CFO), effective April 6.

Explore pearl history, research, quality factors, and more in the GIA Gem Encyclopedia.