I found this rock on the beach on Long Island, NY. It's very light. At first, I thought it was pumice. But it doesn't have many holes. It has a lot of beautiful cracks through which a black shine comes through. There are two spots, in particular (tried to photograph them here) that have a bluish shine to them. A knife scratches it if I push hard. A penny does not, so I guess it's a 5.5 or perhaps a bit higher (I had to push hard). The luster of the shiny parts is sort of...like a pencil tip? I don't know how to describe it.
Any ideas? Did I just pick up a chunk of road tar that made its way into the ocean? Or is it a black opal? 😜 I'm just curious--and so are my kids!
Thanks in advance!