
What are crystals made of?
Crystals are solid minerals formed over thousands (or millions!) of years under Earth’s crust. They develop unique geometric structures due to their atomic arrangement. For example:
- Quartz (like clear quartz or amethyst) is silicon dioxide.
- Calcite forms from calcium carbonate.
Fun Fact: The color and clarity depend on impurities (e.g., iron turns amethyst purple).