Crystals

I studied about crystals last week. "A crystal is a solid that has a definite geometrical shape with straight edges and flat surfaces." - definition from The Usborne Science Encyclopedia 

Did you know that humans eat rock? It's called salt. The solid form of salt is called rock salt, or halite. It is not like the rocks on a driveway or a mountain. Salt is a very soft mineral that forms square- shaped crystals. It is not like my mom's ring that is a diamond and square. Diamonds have to be cut into the shape you want. Salt will form in a square every time. 

We made our own salt crystals. We boiled water and added salt one teaspoon at a time to make a super-saturated solution. Then we poured it into a jar. I added red food coloring to make it look red. We got a pencil, some string and a paper clip and tied them together. We put the pencil on top of the jar and left it alone. After just one afternoon I could see the crystals forming. I left it alone for a week. There were square salt crystals on the string and at the bottom of the jar and on the paper clip. The crystals were pink. I wanted red crystals but that's usually what happens when you color something with red coloring that is white. I will use blue next time.