Matrix:
A rock or mineral that has an embedded crystal or crystals emerging from it.
Specimen:
A mineral of interest to collectors or scientists.
Termination:
The end of a crystal face; the defined ending of a crystal.
Contact:
The place where two crystals come together or meet.
Mineral:
Minerals are usually solid, inorganic, have a crystal structure, and form naturally by geological processes. They posses a chemical structure made up of elements. A mineral can be made of a single chemical element or more usually a compound. Elements can sometimes also be minerals, e.g., gold, diamond, copper, and silver.
Crystal:
The three-dimensional form exhibited by a mineral with defined sides and angles, which are positioned based on its inherent atomic structure.