Nitrates are not geologically widespread, nor are they mineralogically significant, except for two types that are used in explosives and for fertilizer. These are niter, also known as saltpeter, and soda niter.  Both are found in Chile. They are water soluble. During the Civil War, the supply from Chile was cut off by the Union army and the Confederacy made use of niter associated with bat guano found in caves in Tennessee.

I am not a student of metaphysics. However, I am grateful to those who use stones and crystals for healing for the resurgence of interest in rocks. Adamite is a zinc arsenate associiated with joy, love, creativity and enthusiasm. Usually it is a bright yellow green. The best specimens are from Mexico and Namibia.

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