Okay, so it’s not a real word. But it gets the point across, right? We can use candy, rock candy to be specific, to study how crystals form (crystallography).
How to Start: A little background: a crystal is a solid made from molecules that form a repeating pattern. What’s really cool is that as the crystals grow, they form in the shape of that molecular pattern (aka crystal system)!
- Boil 2 cups water.
- Add 4 cups sugar (we used white sugar) over medium-high heat.
- Stir constantly until the sugar dissolves and you get a rolling boil.
- Pour into containers (mason jars work great).
- Add food coloring and flavored syrup, if you want.
- Dip a chop stick in the solution, remove and let fully dry. It will take a day or two.
- Once dry, put the chopstick back into the solution. Use a clothespin to hold the stick in place and about an inch off the bottom of the container.
- Watch your crystals grow!
What to do next: Discuss with your kiddos how they think the crystals grew. Form a hypothesis and then do some research. Hint, key word are: supersaturated, precipitate and evaporation.
What we found: I tried to take a short cut. It failed. I learned. I read that you could wet the stick and roll it in sugar, so you wouldn’t have to wait a day or two for the stick to dry. That didn’t work for us.
Expand it: How can you bring in other content areas?
- Science: Time to dig into some Geology (my fave!). Research the different crystal patterns (or systems). What are they? How many are there? Can you give an example of a mineral from each system? What is the difference between a crystal and a mineral?
- Technology: How are crystals used in technology? Why are crystals used in technology?
- Engineering: What is crystal engineering and why is it so important?
- Arts: Can you draw a picture of your crystals? What about pictures of the different types of crystal systems?
- Math: What shapes do different crystals form? What angles do they have? What patterns?
- Britannica has a couple of good explanations of crystals:
- Geology In provides an overview of the different crystal systems: http://www.geologyin.com/2014/11/crystal-structure-and-crystal-system.html
- The USGS has multiple resources on the use of minerals:
- Here’s a great example of drawing crystals in an art class from Elements in the Art Room: http://elementsoftheartroom.blogspot.com/2018/01/art-rocks-4th-grade-gems-crystals.html