Crystallite

Imagine you have a big cup filled with a bunch of tiny cups stacked on top of each other like a tower. Each small cup is called a crystallite.

Now, these crystallites are like tiny building blocks that make up a bigger structure called a crystal. Just like how legos can be combined to make something bigger, these crystallites can join together to make a big, beautiful crystal.

And just like how different lego shapes can make different things, different types of crystallites can create different types of crystals.

So, basically, crystallites are tiny building blocks that make up crystals. They come in different shapes and sizes and can join together to create all sorts of cool crystals.