a natural occurring solid inorganic substance with a definite chemical composition and crystal structure?

Question

***[isuru]*** · Answer

hi,
 source - Wikipedia
         A mineral is a naturally occurring substance that is solid and stable at room temperature, representable by a chemical formula, usually abiogenic, and has an ordered atomic structure. It is different from a rock, which can be an aggregate of minerals or non-minerals, and does not have a specific chemical composition. The exact definition of a mineral is under debate, especially with respect to the requirement a valid species be abiogenic, and to a lesser extent with regards to it having an ordered atomic structure. The study of minerals is called mineralogy.
  example
           calcite
           gypsum
           talc

***[isuru]*** · Answer

Is this wt u were looking for ?