- The specimen number
- The mineral identity (species, possibly variety)
- Optional: the mineral formula
- Not optional: the mineral locality information, as exactly as possible
- A short description
- Optional: Label design or information indicating the collection from which it comes.
For example, one collector I know numbers several loose crystals of the same mineral from the same locality as follows: 1234-1, 1234-2, 1234, 1234-4. These can then share the same label numbered 1234, with the description including: "Four (4) loose crystals."