Many attractive Sherry colored prismatic lustrous crystals of topaz to 2.3 cm in size coming off of matrix. This is crystallized completely all around and in excellent condition. Minor opal is present. The specimen comes with a previous label from the collection of Ray DeMark.Pismire Wash is a prominent dry drainage located on the eastern side of the Thomas Range in Juab County, Utah. While it does not represent a traditional commercial mine with formal opening and closing dates, the surrounding area has been actively prospected by rockhounds and mineral collectors since its geological features were first documented during mid-19th-century government surveys by explorers like Henry Engelmann in 1859. Geologically, the region is characterized by Tertiary-period volcanic activity dating back approximately 6 to 7 million years. The wash cuts through or runs adjacent to the Topaz Mountain Rhyolite, a light gray volcanic host rock formed from viscous flows and tuffs. Within the small gas cavities and vugs of this host rhyolite, brilliant gemstone crystals formed via vapor-phase deposition. Abundant topaz crystals--ranging from clear specimens that bleach white under direct sunlight to highly sought-after amber or sherry-colored varieties--weather out of the rock matrices and accumulate in large numbers within the loose gravels, washes, and arroyos of the area.
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