Calcite

Calcite is made of calcium carbonate (CaCO3). Generally white to clear, it is easily scratched with knife. Calcite is number 3 on the Mohs Hardness Scale. Most seashells are made of calcite or related minerals. This is the 'lime' of limestone.[1]

## References[edit]

1. ↑ http://wrgis.wr.usgs.gov/docs/parks/rxmin/mineral.html#amphibole