FMF - Friends of Minerals Forum, discussion and message board

[Catahoula]

Hello All, I have a favorite place in the California region of the Mojave Desert to hunt for minerals. The area is to the south-west of Death Valley and Searles by 40 miles. There are volcanic buttes filled with jasper and chalcedony. Some common opal. I found this and had not seen anything like it prior. It is a deep green. Shiny and glossy, but not translucent. It is gemmy to the tongue, not porous. The original was a fist-sized bomb with the end fractured off. It had a white crust over its entirety and the end opposite the fracture is the crusty occurrence you see in the images. The crust ground off easily, but the center is quite hard. There seems to be quite a lot of sand embedded in the glossy as I cannot grind deep enough to get a clear finish. I am awaiting a media to polish the outside and see if it clears up. I get no streak at all on paper or porcelain. It will scratch glass easily, but not steel. What is it?

[alfredo]

Perhaps not what you want to hear but, based on the color, luster, surface texture, interior bubbles, and sand incorporated into some surfaces - I think it's a beer bottle melted in a fire. I've found similar in the past, and took it home for the "interesting rocks" collection, even though technically it's an "anthropogenic rock". But I'm not absolutely 100% certain. There is perhaps some chance it could be a rock partially melted by a lightning strike, although such objects (called "fulgurites") usually look different.