A faceted topaz weighing 22,892.50 carats, making it the largest cut yellow topaz in the world, as well as one of the largest faceted gems in the world. On the left side in the above photo is the Lindsay Uncut Topaz, weighing 70 lbs, and the one on the right is the Freeman Uncut Topaz, weighng 111 lbs. All three stones are part of the Smithsonian Museum's collection (USA).

Characteristics of the gemstone

  The “American Golden Topaz” is an enormous cushion-cut gemstone weighing 4.5785 kg, equivalent to 4.5785 x 1000 x 5 = 22,892.5 carats. The rough stone that weighed 11.8 kg took a long period of almost two years to cut and polish. its hardness is 8 on the Mohs scale. The finished gemstone had 172 facets, with a pleasant light golden brown color and almost flawless clarity and good transparency. The combination of perfect cut, color and clarity in addition to its enormous size has made the American Golden Topaz one of the most renowned faceted gemstones in the world.

History of the American Golden Topaz

   The 11.8 kg (26 lb) enormous rough golden topaz crystal was discovered in Minas Gerais, the fourth largest and the second most populous state situated in the southeast of Brazil. Some of the highest peaks in the country are situated in Minas Gerais, in the southern mountain ranges, and the state is also the source of some of the biggest rivers in Brazil. Minas Gerais is a mineral-rich state, and has large deposits of iron and sizeable deposits of gold and gemstones such as emeralds, topaz and aquamarine. Diamonds were also mined in the state in the past.

The Processing of the American Golden Topaz.

The 11.8 kg rough American Golden Topaz was purchased by the Rockhound Hobbyists of America, who got the stone cut and polished by Leon Agee. It took the master cutter a period of over two years to complete the process. The gemstone was donated to the National Museum of Natural History of the Smithsonian Institution, in Washington DC, in 1988, and is displayed in the Janet Annenberg Hooker Hall of Geology, Gems and Minerals, one of the main galleries in the Museum, together with the “Golden Topaz Sphere” weighing 12,555 carats. The Museum also holds two of the world’s largest uncut Topazes, the 32 kg Lindsay Topaz and the 50 kg Freeman Topaz.