Topaz Mountain is the Southern most portion of Thomas Range. It is characterized by light gray to white rhyolite. The south eastern most point is Topaz Mountain Amphitheater (also know as Topaz Valley or the cove). This is the main and easiest accessible collecting area of the range. Topaz Valley was set aside by the B.L.M. Department of the Interior as a rockhound area. Despite the rumors of it being completely picked over, with hard work and a lot of patience you are often rewarded with some fine clear or sherry colored topaz.
The topaz of topaz mountain fades to colorless when exposed to heat and radiation (the Sun). So, to find the prized sherry colored topaz you have to resort to hard labor. I suggest for the casual collector to bring a 1/4″ screen, rock hammer, and screwdriver. Screen any dirt in washes and around any vegetation. You could easily screen hundreds of clear topaz and some sherry in a days work. Also find any clear topaz on the surface and pry them out with a screwdriver or rock hammer.
If your an avid collector that likes to break up rock and get down to business, I suggest that you bring the following: a heavy hammer (3 lbs +), rock hammer, large chisels (3/4″+),screwdriver, and rock bag.. Attack the mountain by finding soft spots in the rock and hoping to find any cavities. Be aware of signs that may help you. Such as Vegetation in Rhyolite, fracture seams, or open cavities are all good signs you are in a promising area. Be sure to follow the fracture seam, usually sparked off by brownish colored altered hematite. Plugs and frothy rock (both very mineralized Rhyolite) are very good signs your in a cavity. If you follow the signs and be very patient you should be rewarded with many fine sherry colored topaz, and other beautiful minerals.