The Classification and Formation of Crystals

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…grew my crystals from seed crystals). If a solution like this is cooled slowly, a few seeds grow into large ones; but if it is cooled rapidly, numerous seeds form and grow only into tiny crystals. Table salt, purified at a factory by recrystallization, is composed of lots of cubed crystals, which are barely visible with the naked eye; rock salt, formed in a really long time, contains enormous crystals of the same cubed form.