Cleavage describes how a mineral breaks along weak planes within its crystilline scructure .  It can be recognized by looking for 3 different features.

1. Look for large flat surfaces. How many flat planes to you see in each of these two samples?  (Click on each sample to see the answer).
2. Look for a stair-step appearence in the way a sample breaks. (Click on the sample to see the answer).
3. Look for a "winking" of light reflection as you rotate the sample in the light.  (Click on sample for demonstration)