I think Calcite. Calcite is 3 on the hardness scale and sometimes you can break it into cubes. The difference between Calcite and Quartz is that Calcite is a milky white.
Cleavage is most often used with the following 3 meanings: MITOSIS: a phase during Mitosis when cells split and multiply GEOLOGY: The splitting of a complex crystal/mineral formation into a simpler...
One of the most well know minerals that does not have cleavage is quartz. There are several others as well. When a mineral forms some have planes of weakness where they will naturally break apart....