* Basalt: A common extrusive igneous rock, basalt can range from black to dark grey, sometimes with a greenish tinge due to the presence of olivine or pyroxene minerals.
* Gabbro: This is the intrusive equivalent of basalt. It can also be dark grey to black, sometimes with greenish hues.
* Diorite: This rock is intermediate in composition and can have a greenish-black appearance if it contains significant amounts of hornblende.
* Peridotite: A deep-seated igneous rock that is often dark green to black due to its high olivine content.
It's important to note that color alone isn't enough to identify a rock. You need to consider other characteristics like texture (grain size, presence of crystals), mineral composition, and the overall context of the rock's occurrence.
