Like the topic,I am just curious about what ebony is?

Wood.

I'm not sure what it is neither.

http://en.wikipedia.org/wiki/Ebony, http://www.uesp.net/wiki/Lore:Ebony, similar to the glass of glass armors and weapons.

When you can mine it im pretty sure its not wood. if you dont believe go to the very tip top peak of High Hrothgar and see what ore is up there.

Ebony and glass are minerals because you can mine them. Its not the same as the ebony wood we use for piano keys.

They are some sort of fantasy volcanic substances and there were lots of ebony and volcanic glass mines around the volcano in Morrowind.

Same name, different material, just like malachite, moonstone, and corundum, which are gemstones in our world, but are apparently refinable metals in TES.

Got it ,thanks to all the above.