Answer:
It means that it always contains certain elements and it always contains elements in definite proportions.
Explanation:
A mineral has five characteristics: definite chemical composition, naturally occurring, inorganic, solid and ordered internal structure.
Definite chemical composition means that every time a mineral is naturally created, its <u>chemical formula is always the same</u>, there are n<u>o modifications on the number of atoms </u>of the elements that are contained in it, and those <u>elements do not change</u>.
