Metallic Chalcopyrite on Calcite

SD Crystal - Calcite specimen #crystal

Ah, the persistent calcite vs. quartz debate! So this isn’t a definitive test to determine just ANY clear mineral; there are plenty of clear minerals that would perform differently on this one simple test. But, if someone tells you “hey, this is EITHER a quartz or a calcite, can you tell which?” this is one indicator test. If you want one quick visual test that would help, gemmy calcite is so doubly refractive that it will often show doubled images, but you might have to test it at a few differe

Here is a GREAT piece of NY calcite that broke apart! I was in a great spot for clear calcite for a while, it has lots of marcasite “needles” in it of all colors! Here is a gold colored one in a natural perfect fractured slab!! #Dig #herkimerdiamond #ny | Will Zier