Black Sands Under Blacklight

摘要

Experienced gold panners will periodically check all minerals, light and heavy, that they might have in their pan, especially when they enter a new region. They can usually identify most minerals with the aid of a hand lens. However, the typical gold panner is interested only in gold and platinum-group metals, and will discard the black sand concentrates. It might be wise to discard the black sands into a bucket, then go over them thoroughly when time permits. Gold panners in North Carolina must be on the lookout for rubies, and those in Montana must look for sapphires. Panners have found diamonds in Arkansas, Colorado, Wyoming, and California. Many stream courses in Brazil, Venezuela, and South Africa are panned exclusively for diamonds. Other minerals in the pan might not have value in themselves, but when they occur in abundance they may signal the presence of a nearby deposit which could have considerable value. For example, unusual quantities of titanium, tantalum, or rare earth minerals would get the attention of most miners.