How to Grow Black Crystals 2

Black crystals include translucent ones, like black diamonds or smoky quartz, or opaque crystals, like anthracite. You can take most crystal recipes and use them to grow black crystals.

The Secret to Black Crystals

While it’s easy growing crystals in rainbow colors, black is a little trickier because a lot of black dyes are really dark versions of other colors. Your best bet is using liquid black food coloring because it’s meant to appear black even when it’s diluted. If you use a lot of colorant, you get opaque crystals. A smaller amount gives you see-through true black (not gray).

But, there is a catch! Crystals naturally exclude contaminants. So, even mixing in a lot of dye doesn’t guarantee black crystals. Covalent compounds, like sugar, more readily accept coloring. Ionic compounds, like salt and borax, remain colorless.

With colorless crystals, use a black pipe cleaner, rock, or black paper as a base. The pipe cleaner works great as a substrate, either hanging into the crystal solution or else coiled up to form a fuzzy “rock.” While not essential, this gives more depth to the black color. For added interest, wrap the black pipe cleaner with a metallic silver, black, or colored stick to produce crystals that flash in the light.

Translucent Black Crystal Recipes

You can use most simple crystal recipes, as long as they normally produce clear crystals. Good examples of materials include sugar, borax, or Epsom salts. Don’t use a chemical that produces a cloudy effect (e.g., calcium carbonate) unless you want gray instead of black.

• Borax, salt, or sugar
• Hot water
• Black pipe cleaners
• Food coloring (optional)
• Container

1. First, prepare the pipe cleaner so it fits in the container. It doesn’t matter what shape you make, but you don’t want it to touch the sides of the container or else it will be hard to remove the crystals. For easy removal, wrap the pipe cleaner around a butter knife and let it hang into the jar so that it’s not touching the sides or bottom. Once you’re satisfied with the base, remove it and set it aside.
2. Next, prepare the crystal solution. Fill the jar with very hot water. Stir in borax until it stops dissolving. You can dissolve about 3 tablespoons of borax for 1 cup of water. It’s not a big deal if there is a little undissolved borax left.
3. If you like, add black food coloring. Using a few drops may produce translucent black crystals. Or, it may not incorporate into the crystal structure. Experiment!
4. Put the pipe cleaner in the container. If you added food coloring, expect the solution to be too dark to watch the crystals grow. Wait several hour or overnight before removing the crystals.
5. When the crystals have grown, set them onto a paper towel to dry.
6. Once the crystals are completely dry, you can seal them to preserve them.

How to Grow Opaque Black Crystals

Either grow colorless crystals that incorporate dye, like sugar with food coloring, or else grow crystals that are so dark that they appear opaque black. Copper acetate crystals are blue-green when tiny, but grow into larger crystals that appear solid black.

Black Sugar Crystals

• 1-1/2 cups sugar
• 1/2 cup boiling water
• black food coloring
• licorice flavoring (optional)

1. Dissolve the sugar in the boiling water and add a lot of black food coloring. If the solution isn’t opaque, don’t expect the crystals will be either!
2. Since sugar crystals are edible, add flavoring, if desired.
3. Set the solution somewhere free of dust and vibrations.

If you like, hang a string or rod into the liquid that offers a place for crystal growth. Then, remove unwanted crystals that grow on the sides and bottom of the container. The time it takes for crystals depends on the rate of cooling and evaporation. If you refrigerate the solution, you get lots of crystals quickly, but they are fairly small. Slow cooling and evaporation yields larger crystals.

Black Copper Acetate Crystals

• 20 grams copper acetate monohydrate
• ~200 milliliter hot water

1. Dissolve the copper acetate in hot water. It takes about 200 milliliters, but use the minimum amount necessary for dissolving all of the salt. This results in a saturated solution.
2. Next, you want a seed crystal. This serves as a substrate for growing a large single crystal. You want a large single crystal so that it gains enough size that it becomes black. Pour a small amount of the solution onto a small place or shallow bowl. After a couple of hours, select the best crystal (or a few).
3. Either tie the seed crystal to a nylon line and suspend it in the larger container of crystal solution or else drop the seed crystal into the liquid. While trickier, tying the crystal onto the string gives you a big advantage, since you can pull it out and check on its progress.

When the crystal reaches sufficient size, remove it from the liquid and let it dry.