Rock candy is a simple sugar candy that can double as a science experiment. The process can take up to a week, but it’s fun to watch the sugar crystals growing over time. Note that the exact quantity of sugar syrup you will use depends on the size of the jar you have. If you want to make several pieces of rock candy, use multiple jars and skewers, and double or triple the sugar syrup solution as necessary. For easily printable instructions, please see the rock candy recipe
. Begin by assembling your ingredients:
- 2 cups water
- 4 cups granulated sugar
- 1/2-1 tsp flavoring extract or oil (optional)
- food coloring (optional)
- glass jar
- skewer or thread (see below)
Prepare your materials: wash a glass jar thoroughly with hot water to clean it. To make rock candy on a wooden stick, cut a thin skewer until it is slightly taller than your jar. Use clothespins balanced across the top of the jar to clip it into place. This method is illustrated above.
Alternately, you can make your rock candy on a string instead. Cut a length of thick cotton thread or kitchen twine a few inches longer than the height of the jar, and tape it to a pencil. Place the pencil across the lip of the jar, and wind it until the thread is hanging about 1 inch from the bottom of the jar. Attach a paper clip to the bottom of the thread to weigh it and ensure it hangs straight down.