Basalt

[halcyon days]

Can anyone tell me if basalt is a dark glossy volcanic rock please

[reddinouk]

yes.
volcanic, usually grey but can be green or black, and glassy or microcrystalline
Spectacular examples include Fingals cave and the Giants causeway

[heathfield]

Basalt can be glossy when it's not been exposed to the elements, but it dulls with weathering. There's a sample shown here.

[halcyon days]

Thankyou very much