ELI5: Explain Like I'm 5

Crystal twinning

Have you ever played with LEGOs? When you put two or more LEGO pieces together to make something bigger, that's kind of like what happens when crystals twin.

Crystals are really small pieces of matter that are made up of repeating patterns of molecules. Sometimes, when crystals are forming, they can run into another crystal that's also forming, and they can stick together. When this happens, it's called twinning.

Just like with LEGOs, when crystals twin, they can create bigger and more complex shapes. Sometimes the twinning produces symmetrical shapes, like a mirror image of itself. Other times, it can produce strange and irregular shapes.

Scientists are really interested in twinning because it can give them clues about the formation and growth of crystals. But for now, just remember that twinning is when two crystals stick together to create something bigger, like putting together LEGOs.
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