Crystal Growth
Crystal growth is what happens when tiny particles in a liquid slowly stack together into a solid shape.
When you stack sugar cubes in a jar, each cube locks onto the one below it in a neat grid. Crystal growth works the same way. Tiny bits in a liquid settle into place, one by one, building a solid shape with a pattern that repeats. The liquid is the jar, and the bits are the sugar cubes snapping into their spots.
Explaining crystal growth by grade level
Think about stirring salt into warm water until no more dissolves. As the water cools, the salt comes back out. It forms small, shiny blocks you can see and touch. Those blocks are crystals growing from the water.
Projects that explore crystal growth
In a crystal garden, tiny particles join together in a repeating pattern — and a few kitchen ingredients make it happen overnight. Salt provides the building material. Bluing supplies the tiny particles that crystals anchor to, and ammonia speeds up evaporation so the whole structure forms faster.
When dissolved particles settle into a repeating pattern, crystals take shape — but temperature decides what kind. Crystals near a fireplace grew the largest. The cold crystals grew the most in number. Heat and chill each push growth in a different direction, shaping both size and quantity.
Salt crystals form as water evaporates from a salty mixture, leaving solid structures behind. Certain chemicals change how large those crystals get. Bowls without ammonia produced small crystals about 2.5 mm tall. The bowl with the most ammonia grew crystals over 8 mm tall — enough to overflow the bowl entirely.
As water evaporates, it leaves behind crystal deposits — the same basic process that builds stalactites and stalagmites in caves. Salt water creeps along the yarn and drips down onto a plate below. Over several days, a tiny stalactite grows from the yarn while a stalagmite builds up on the plate.
When Borax dissolves in hot water and the mixture cools, the dissolved Borax comes out of solution and stacks into solid crystal structures. Sparkling crystals coat whatever pipe cleaner shape you dipped in. Add food coloring first to create rainbow effects across the finished form.
You dissolve Borax in hot water and pour it into a hollow eggshell. As the solution cools, crystals form along the inside walls. The result looks like a miniature geode (a rock filled with crystal points).