There are actually 5 key properties that define a mineral, not six. These are:

1. Naturally Occurring: Minerals form through natural geological processes, not in a lab.

2. Inorganic: They are not made of living organisms or their remains.

3. Solid: Minerals have a definite shape and volume.

4. Crystalline Structure: Their atoms are arranged in an orderly, repeating pattern.

5. Definite Chemical Composition: Each mineral has a specific chemical formula that determines its composition.

Bonus: While not a strict requirement, minerals often have a consistent physical appearance and unique properties like hardness, cleavage, and luster.

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