Emerald, a favorite among precious gems, is actually a variety of beryl. The pronunciation of beryl is the same as if you were saying “barrel.” Other common names for beryl include aquamarine (blue), heliodor (yellow-green) and morganite (pink). A wide range of beryl is housed in the Dice Mineral Museum right here on Calvin College’s campus.

Beryl is a beryllium-aluminum-silicate, and its formula is Be3Al2(SiO3)6. This mineral forms hexagonal crystals. On an exponential scale that goes from one to 10 (with 10 being the hardest) Beryl has a hardness of eight, so (as you can imagine) it is a pretty hard mineral.

Beryl can be found all over the world. The largest one found was discovered in Malakialina, Madagascar. It is 59 feet long, 11 feet wide and weighs about 400 tons.

Beryl commonly forms in granitic pegmatites. Granitic pegmatites start with really old rocks. Some of those rocks get melted and rehardened, but it takes a very long time for them to cool down enough to become a hard rock again. Because of that, the minerals in the “melt” are able to grow really big crystals because they have a lot of time to grow. We call these very coarse-grained rocks pegmatites. The minerals in these rocks combine to form a rock that we refer to as granite.

Beryl crystals form from the leftover elements in the last bit of unmelted rock. Come see this mineral for yourself in the Dice Mineral Museum, located on the first floor of North Hall.