Shiny Black Beach Rock

[Sonoch]

Went to the beach a few days back and found some gorgerous rocks. I've looked through my rock identification books, but I'm more of a shell expert. Anyone know what's up with this baby?

It's insanely smooth and not at all brittle. It's black and the flat bits shine in the light, but there are some bumps.

 

Amazon Forum Fav 👍

A History of Mining on the Kenai Peninsula, Alaska - Grab it through Amazon!

[Tony in SC]

Try posting over on the Rocks and Gems forum. A lot more rock people over there.

 

[smokeythecat]

It's probably anthracite coal, used in the old steam ships. It washed up from time to time.