How long did it take to form this calcite pipe formation? Not long. #calcite #geology #evolution #creationism | Lost World Museum

Calcite with Pyrite - Chenzhou, China

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