There is only one known commercial occurrence of gem-quality red beryl in the world: the Ruby Violet (or Red Beryl) mine in the Wah Wah Mountains of Beaver County, Utah. The beryl is found mostly along fractures (often clay-filled) in a topaz rhyolite. It crystallized as a vapor-phase mineral from the reaction between rhyolite-derived gases, vapors originating from heated ground waters, and preexisting minerals and volcanic glass in the rhyolite. Production of red beryl over the past 25 years is estimated to be more than 60,000 carats, of which about 10% was facetable. Exploration and evaluation programs undertaken by two mining companies from 1994 to 2001, combined with field studies by some of the authors and others, have resulted in a greater understanding of the geology of the Ruby Violet deposit and the potential for productive areas beyond the current mine site.