In April 2014, a team from GIA visited major emerald and tourmaline sources in Brazil. One of the most exciting mines the team visited was the Cruzeiro tourmaline mine in the state of Minas Gerais, ...

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 ...

Although quartz is known to host a diverse assortment of mineral inclusions, well-formed bladed kyanite inclusions in quartz are rarely observed. At first glance, the 7.83 ct blue-colored stone in the ...

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 ...

Presents findings from observations of oval-, pear-, and marquise-shaped diamonds, laying the groundwork for a fancy cut grading system.

Apart from the red variety, this gem is also found in green, pink, and various combinations of these colors. About 20 years ago, there was even a discovery of cuprian tourmaline in western Nigeria ...

At the earth’s surface, graphite is the stable crystalline form of carbon, with a density of 2.26 g/cm 3. Diamond is a much more compact form of carbon, with a density of 3.52 g/cm 3, 56% higher than ...

Photoluminescence (PL) spectroscopy is frequently mentioned in the gemological literature, but its relevance to the wider trade audience is rarely discussed. Due to the possibility of an undisclosed ...

Along with the skyrocketing price of white nephrite, there is also a developing market for green nephrite in China. However, limited local supply has forced the Chinese to seek outside resources, ...

When people hear the word diamond, colorless diamonds generally come to mind—not the more exotic colors discussed earlier in this article series. In purchasing a diamond, they are likely to choose one ...

There’s an old saying that whatever you are doing at the start of the year will reflect on the rest of the year. Hopefully this is true, because for the authors, 2014 truly started out right. The ...

Natural-color pink diamonds are exceptional treasures. The lead article in this issue, based on GIA’s database of more than 90,000 diamonds in the pink, orangy pink, purple, red, and brown color ...