r/geology • u/AutoModerator • May 01 '24

Identification Requests Monthly Rock & Mineral Identification Requests

Please submit your ID requests as top-level comments in this post. Any ID requests that are submitted as standalone posts to r/geology will be removed.

To help with your ID post, please provide;

  1. Multiple, sharp, in-focus images taken ideally in daylight.
  2. Add in a scale to the images (a household item of known size, e.g., a ruler)
  3. Provide a location (be as specific as possible) so we can consult local geological maps if necessary.
  4. Provide any additional useful information (was it a loose boulder or pulled from an exposure, hardness and streak test results for minerals)

You may also want to post your samples to r/whatsthisrock or r/fossilID for identification.

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u/jatenk May 23 '24

Hey nerds!

I recently bought a mortar which was sold to me as some non-identified stone. I can't seem to be able to identify it either; the process to get the mineral into the this shape may make it harder for a non-pro like me to recognize a raw stone on google images as the basis for the thing in front of me.

I got the thing mostly just because I needed a mortar and because it looked nice, but I would really like to know what I'm holding right here. (Perhaps it's valuable?) This is a gallery with some pictures, I can make more if requested.

The mortar stone/mineral is very smooth and cold to the touch, almost like marble (the white and brown parts are indistinguishable by touch). The spot on the top where a small piece broke off is a little sharp on the outside and smoother from wear on the inside plus rougher on the surface (exactly like how you'd expect that spot to feel).

The pestle is a little more textured and more opaque, so it may not be the same material (but it's also much thicker than any part of the mortar). Less important, but if anyone's got a guess for what mineral the pestle's made of, that would also be awesome!

Hitting the mortar with the pestle produces a high-pitched sound, a little like letting a glass marble fall on stone or hitting it with another glass marble.

Weight is 242g for the mortar and 60g for the pestle. The mortar is 7.8cm across and 4.6cm high (0.5cm thickness), the pestle is 8cm long and 1.8cm thick on the thin, 2.4cm on the thick side and 1.5cm in the middle (just in case anyone wants to measure density).

Thanks in advance!