Featured Gem Topaz

Honey yellow. Fiery orange. Cyclamen pink. Icy blue. In warm or cool tones, topaz is a lustrous and brilliant gem.

Colorless topaz treated to blue is a mass-market gem. Fine pink-to-red, purple, or orange gems are one-of-a-kind pieces. Top sources include Ouro Prêto, Brazil, and Russia's Ural Mountains.

BIRTHSTONE: November

overview

Topaz actually has an exceptionally wide color range that, besides brown, includes various tones and saturations of blue, green, yellow, orange, red, pink, and purple. Colorless topaz is plentiful, and is often treated to give it a blue color. Topaz is also pleochroic, meaning that the gem can show different colors in different crystal directions.

10 mev

Irradiating colorless topaz with electrons at energy of 10 million electron volts creates a sky blue color.

1768

The royal court in Portugal celebrates the discovery of Imperial topaz in 1768.

271 kilos

Opal contains up to 20% water trapped in its silica structure.

QUALITY FACTORS

Topaz comes in a variety of colors from shades of blue to the rare reddish imperial colors.

color

The most valued topaz colors are orangy red to red. Blue gems are widely available.

clarity

Topaz used in jewelry is typically eye clean with no visible inclusions.

cut

Topaz crystals are usually columnar, and cut as oval or pear shapes to improve yield.

carat weight

Topaz can often forms as large crystals. These can yield sizeable cut gems.