Question about cleavage?

Question

I don't understand how a cleavage split in minerals (crystals) is considered to a "plane". A plane is supposed to be connected by atoms like those unit cell diagrams. A crystal face is a "plane" because it is connected by atoms. But cleavage breaks those connections in certain instances. So why is cleavage a plane?
Any help greatly received!

Question about crystal cleavage

Answer 1

Why wouldn't the plane also be connected by atoms? Cleavage occurs at a point of weakness in the structure. A cleavage plane would almost be akin to a crystal face so would perhaps have some of the same properties.

You also have to remember that sometimes terminology is not born of accuracy.

I am not a mineralogist. Your best bet is to ask your professor.

Answer 2

Avio is right. It is a term that means a flat surface. In certain minerals there are certain connections in the crystalline structure that break apart easier. Since crystals are atoms that align in a regular pattern that tends to repeat, the cleavage is usually planar. If you ever look at an cornfield or an orchard where the trees are evenly spaced, you might see that as you drive past there are different lines where you can see through where no trees are planted. If these trees were crystals, the cleavage plane might be those lines where tree are not planted. Since crystals are three dimensional you have to extend the lines in three dimensions to make them planes.

Answer 3

You're thinking too hard. "Plane" just means "flat surface." So when you crack a rock that has a crystal structure that cleaves easily, it cracks along a flat surface. That is what is called a cleavage plane. It just means it's flat.

Answer 4

You should think about changing the name of your question, because the type of people looking to answer it probably won't know what your talking about.