How to Grow Crystals
It's Easy and Fun to Grow Crystals
Anyone can grow their own crystals. It's fun, easy, and educational. You don't need to buy a kit or any unusual chemicals to grow great crystals. The only materials you need are ones you probably already have at home. Let's get started!
[Photo: Copper sulfate crystals are bright blue crystals that are easy to grow. (Stephanb, wikipedia.org)]
What Is a Crystal?
A crystal is a substance that has a highly ordered internal structure. Crystals can be composed of atoms, molecules, or ions.
Examples of common crystals include sugar and salt. Most gemstones are crystals, such as diamonds, emeralds, and rubies. Some materials that are called 'crystal' but really aren't include all types of glass and faceted plastic. Crystals can be shaped or cut, but their internal repeating structure often gives them a characteristic shape without any treatment.
[Photo: Quartz crystals (William Roesly, www.morguefile.com)]
Basics of Growing Crystals
What You Need to Know about Growing Crystals
Crystals that you can grow at home are grown from solutions in water. To grow a crystal, you dissolve a chemical in water, then either evaporate the water or cool the solution so that the substance starts to crystallize. Usually you hang a string or a seed crystal in the growing solution to provide a surface for the crystals to form. You want water to be able to evaporate from the solution, so you can't seal the container. However, you can place a coffee filter or paper towel over your solution to keep it clean. Crystals grow best if they are undisturbed. You can watch them grow, but don't pick up the container or shake it.
Crystals on Amazon
Easy Crystals You Can Grow Yourself
Safe, Non-Toxic Crystals to Get You Started
There are many types of crystals that you can grow, including some that come from foods. Even young children can grow these crystals. The crystal solutions start out very hot, however, so adult supervision is important.
- Pour 1/2 cup of hot tap water into a clean jar. Boiling water is even better, but you don't absolutely need it, so if you're doing this project with younger investigators, feel free to use tap water.
- Stir in alum (located on the spice aisle of the grocery store as a pickling ingredient) until no more will dissolve ( this can be up to 2-1/2 T).
- Let the jar rest undisturbed overnight or for several hours.
- Pour the liquid from this jar into a clean jar. Try not to get any undissolved solid material in the new jar.
- There will be crystals on the bottom of the original jar. Select the best of these and tie a nylon fishing line around it.
- Hang the crystal in the second jar so that it is covered by the liquid, but not touching the bottom or sides of the container.
- Allow the crystal to grow until it stops growing or until you are pleased with it.
- Remove the finished crystal and allow it to dry.
- Add salt to boiling hot water until no more will dissolve. The temperature is important, since much more salt will dissolve with even a couple degrees hotter water.
- For fast crystal, soak a piece of cloth or cardboard in the salt solution, then set it in a sunny, dry spot to dry. Numerous tiny salt crystals will form on the surface of the cardboard.
- For larger crystals, you need a seed crystal. Get a seed crystal by pouring a small amount of this solution onto a saucer. Let the liquid evaporate. Carefully scrape the best crystal from the saucer and attach it to a nylon line.
- Tie the other end of the line to a pencil or butter knife and hang the crystal in the growing solution.
- The best salt crystals take several days to weeks to grow. Allow the solution to sit undisturbed in a cool, dry location. Remove the crystal when you are pleased with it or when it stops growing.
- Stir 3 cups of sugar into 1 cup of boiling water. Keep stirring until as much sugar has dissolved as possible. You can add food coloring to the solution if you like.
- Pour the solution into the container you have selected for growing the crystal. Avoid getting any undissolved sugar in this container, since the sugar will provide a growing surface for the crystals, causing them to grow on your container.
- Suspend a wooden skewer or rough string into the solution.
- Allow the solution to sit undisturbed.
[Photo: Sugar crystals or rock candy can be colored with food coloring and can be eaten. (Douglas Whitaker, wikipedia.org)]
Rock candy is good enough to eat! (Andreas Praefcke)
Grow a Borax Crystal Snowflake
All you need to do is mix equal parts table salt, vinegar, hot water, laundry bluing if you have it (if you don't, it's ok), pour it onto a plate, then set an empty toilet paper roll on the plate. If you like, you can dot the paper towel with food coloring. The cut edges at the top increase the surface area to make it look sort of like a tree. Depending on your humidity, you should see crystals in about a day.
More Crystal Recipes You Can Try
If you have mastered the basics of growing crystals, why not try these crystal projects?
- Borax Crystal Snowflake
Grow your own snowflake-shaped crystal ornament overnight.
- Charcoal Crystal Garden
Classic multi-colored crystal project made with charcoal, water, vinegar, salt, and laundry bluing.
- Benzoic Acid Snow Globe
Make your own snowglobe of chemical 'snow' crystals that won't melt.
- Quick Crystal Projects
Many crystals take days or weeks to grow. These projects only take minutes or hours to produce crystals.
- Copper Sulfate Crystals
These are the blue crystals shown at the beginning of this lens. Copper sulfate crystals are easy and safe to grow, plus they are naturally bright blue.
Solutions to Common Crystal Growing Problems
When Crystals Won't Grow
There are three main problems you may encounter with your crystals.
If you have an impurity (e.g., dishes weren't quite clean, chemicals weren't pure, or possibly you made a mistake with a chemical), your crystals may not grow or else they might not look like you had expected. There isn't much you can do to fix this problem except to start over, but before you do, eliminate the other main causes of problems.
Solution Not Saturated
Usually crystals don't grow because there wasn't enough crystal material dissolved in the water. You can concentrate an existing solution by increasing the rate of evaporation of the solution. The best way to achieve this is by improving the air circulation around the crystal solution. Placing the solution near a fan would work, for example. Lowering the temperature of the solution may help, too. This doesn't speed evaporation, but sometimes crystals will fall out of solution as it becomes cooler. Try refrigerating your crystals.
Another common problem you may encounter is crystals growing on the bottom of the container and not on your string. This occurs when the solution contained undissolved material. One way to lessen the chance of this happening is to filter your solution through a coffee filter or paper towel.
Citric Acid Crystals (Jan Homann)
More About Crystals
- Crystal Photo Gallery
See photographs of different types of crystals.
- Crystal Growing Quiz
Test your crystal growing know-how with this fun multiple-choice quiz.
- Types of Crystals
Crystals can be categorized according to their structures or properties.
- Crystal Science Project Ideas
Love crystals? Maybe you should consider doing a science fair project using them.
Crystallization of Copper Sulfate
Your Opinion, Please
This lens includes recipes for growing alum, sugar, and salt crystals, plus a video tutorial for growing salt and vinegar crystals overnight. What other types of crystals do you most want to grow?
What Type of Crystals Do You Want to Grow?
Vote for the Best Crystal Growing Kit - ... or add one to the list!
Let your voice be heard - help other people grow crystals! You can vote these kits and books that describe how to grow your own crystals up or down the list or add suggestions of your own.
Easy Salt Crystal Garden
Mix ammonia, salt and laundry bluing to make this crystal chemical garden.