Birthstone Feature: This Remarkable Brazilian Amethyst Weighs in at 401 Carats

Flaunting an intense vivid purple colour with flashes of red, this 401.52-carat stunner is one of the finest and largest faceted amethysts in the National Gem Collection at the Smithsonian’s National Museum of Natural History in Washington, DC.


The Brazilian-sourced, emerald-cut gem was a gift from the Smithsonian Gemstone Collectors group in 2012 and checks all the boxes for what a Smithsonian-quality gem should be. In addition to its impressive size, it displays superb colour, clarity and cut.

Amethyst is February's official birthstone and the most coveted variety of quartz. The gem is colourless in its pure state, but gets its purple colour from a few atoms of iron displacing some of the silicon in the gem’s molecular structure. These traces of iron can give amethyst a wide range of colours, from almost white to deep purple.

Amethyst has been coveted for thousands of years and is one of the oldest recorded gemstones. Amethysts have been recovered from ancient Egyptian tombs and were prized by the Greeks, Romans, Babylonians and Hebrews.

The colour purple was traditionally the colour of royalty, and amethyst was used to adorn the richest and most powerful monarchs and rulers. The English revered the stone for its majestic properties — creating emblems and insignia featuring amethysts during the Middle Ages to symbolize royalty.

Amethyst gets its name from the Greek word “amethystos,” which literally means “not to intoxicate.” Apparently, the Greeks believed amethyst could reverse the effects of drunkenness. Other characteristics attributed to amethyst include peace, balance, courage, stability and inner strength.

The colour rating of an amethyst is determined by hue, tone and saturation. Hue is the colour; tone is relative lightness or darkness of the colour; and saturation relates to the colour's intensity, from dull to vivid.

While Brazil is the primary source of this gemstone, fine-quality amethysts also can be found in parts of Zambia, Mexico, Uruguay, Italy, Germany, Canada, Maine, Colorado, North Carolina and Pennsylvania.

Credit: Photo by Ken Larsen / Smithsonian.