Question: Hello. I'm collecting crystals and I would like to know how they are formed ?

Martin Ward answered on 6 Feb 2021:

I assume that the crystals you collect are geological crystals, things like quartz etc.

A lot of these types of crystals are formed when the molten material cools nice and slowly and when it is cooled enough the molecules in the material group together and magically organize themselves to form a tiny crystal. When the material continues to cool down then the small seed crystal grows larger and larger. Other crystals formed from liquids follow a similar process