Topic: geology et al
In spite of the fact that I was going to put mineralogy on the back burner, I find myself reading in this discipline again.
I got a letter from someone who saw my website and is looking for a piece of minnesotaite. Now I have lived in MN all my life and my family owned a rock shop since...probably before I was born...but this one was new to me. It is an iron rich talc found in Saint Louis County. There are over 4000 named minerals, the biggest percentage of which are rare or extremely rare.
Another one I was reading about today was either new to me or I hadn't thought about it in a while. Electrum is a natural alloy of gold and silver and was used by the ancients to make coins. Sometimes there are other metals such as copper in its composition. It is a good conductor of electricity, hence the name..