Answer: Internalized Crystal Structure
Step-by-step explanation:
"The exact and unique arrangement of atoms, ions or ionic groups is the characteristic feature of each crystallized mineral."
- S.K. Haldar & Josip Tisljar, authors of Mineralogy and Petrology
A mineral's unique and specific crystal structure determines the physical properties such as color, hardness, density, luster, crystal form, cleavage and fracture.