Azurite is a blue copper mineral with the chemical formula It forms monoclinic crystals. Azurite weathers into malachite. Azurite is used as a pigment, in jewelry, and as a decorative stone. This stone is called "Velvet Beauty" from Bisbee, Arizona.
If I understood the material correctly, these trees have actually turned into agates over the years. When I was a child, my grandmother and I used to collect agates on the shores of Lake Superior in Michigan.
Ethiopian opal is still a new gemstone. Ethiopian opal is quite unique and different from more common Australian and Mexican opal. Not many people know about this opal yet. I am a gem cutter and have worked.