Mineralogists define minerals based on five key features, not four:

1. Naturally Occurring: Minerals must form through natural processes, not created in a laboratory.

2. Inorganic: Minerals are not derived from living organisms.

3. Solid: Minerals exist in a solid state at standard conditions.

4. Crystalline Structure: Minerals have a specific, ordered atomic arrangement.

5. Definite Chemical Composition: Minerals have a fixed or variable but defined chemical formula.

Let me know if you'd like more information on any of these features!