I just looked up zeolite and your guess looks like the most likely suggestion on the crystal look. My friend knows basalt well and assures me it isn't that. What kind of metals spew from a volcano around the Shasta area? Maybe someone knows some kind of test for metals.
Hello would someone please help me identify this specimen? It was found by my friend and is hers. She has been a rock hound from a child. That was 44 years ago. This was found in a volcanic area in California, high up as she could climb towards the spewing area. It is as heavy as Iron yet has...