Chalmers Topaz
Encyclopedia
The Chalmer's Topaz is a topaz
gem weighting 5,899.5-carats
located in Chicago, Illinois' Grainger Hall of Gems, in the Field Museum of Natural History
. It was named for former Field Museum trustee William J. Chalmers and is one of the largest cut topaz gems in the world.
Topaz
Topaz is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO42. Topaz crystallizes in the orthorhombic system and its crystals are mostly prismatic terminated by pyramidal and other faces.-Color and varieties:...
gem weighting 5,899.5-carats
Carat (mass)
The carat is a unit of mass equal to 200 mg and is used for measuring gemstones and pearls.The current definition, sometimes known as the metric carat, was adopted in 1907 at the Fourth General Conference on Weights and Measures, and soon afterward in many countries around the world...
located in Chicago, Illinois' Grainger Hall of Gems, in the Field Museum of Natural History
Field Museum of Natural History
The Field Museum of Natural History is located in Chicago, Illinois, USA. It sits on Lake Shore Drive next to Lake Michigan, part of a scenic complex known as the Museum Campus Chicago...
. It was named for former Field Museum trustee William J. Chalmers and is one of the largest cut topaz gems in the world.