Purnell

Now for something new. In contrast to the lighter-colored igneous rocks you have seen so far, this one is very dark in color. This is a good example of a gabbro. If you look closely, you can see the individual crystals, which means it is phaneritic too. When it is polished, it looks black, but it is actually composed of predominantly dark grey anorthite minerals along with black hornblende minerals.