Your favorite kind of hard rock?

Sorry for being off-topic, but today I received an interesting video - one guy made himself a digital accordion from the wreckage of a synthesizer. Please note that on the guitar neck he used buttons from TV remotes; I liked this the most)

House of the Rising Sun

youtu.be/qlyQvXiKpnU

@Dukedog said in #11:
> Gneiss is nice.

I wouldn't take that for granite.

Cinnabar.

The Rock!!

Obsidian