Topaz Mountain II

Topaz Mountain is located on the southern end of the Thomas Range. This range is very popular to rock collecting enthusiasts. Topaz, Utah's state gem; is a semiprecious gemstone that occurs as very hard transparent crystals in a variety of colors. The Topaz crystals at Topaz Mountain are naturally amber colored, but become colorless after exposed to sunlight. The crystals formed within cavities of the Topaz Mountain Rhyolite, a volcanic rock which erupted approximately six to seven million years ago (Tertiary Period) from volcanic vents along faults in the area.
The best time to search for topaz crystals is actually at night, using your flashlight to catch the glittering rocks on the surface of the ground. In daylight they are the same color as the ground.