March 2024 - Almandine Garnet

March 2024 - Almandine Garnet

People have been using garnets in jewelry since the time of the Egyptian pharaohs. They’re typically dark red, but garnets can come in a range of colors from yellow to orange, and even green. That’s because their chemical composition can vary a lot, while still technically being classified as a garnet – they’re kinda like a whole bunch of crystals in a trenchcoat.
  • Chemical Formula: Fe3Al2Si3O12
  • Mohs Hardness Scale: 7 

People think of garnets as just one thing, but they’re actually more like a handful of minerals all stuffed into a trenchcoat. They’re usually red, but can be lots of other colors, too. That’s because they can have tons of different metal ions in their chemical formula, but still look and act like a garnet.

And while they look lovely as jewelry, they’re prized for more than just their looks. Garnets can be used to study how areas of our planet formed millions of years ago. They’ll only crystallize at a certain temperature and pressure, so when geologists  nd garnets in layers of rock, they know just how hot it got there.

See all articles in List of Rocks