How to Make Glow in the Dark Crystals

This quartz crystal glows in the dark. It's easy to replicate the technique to make your own crystals and gems glow.
This quartz crystal glows in the dark. It’s easy to replicate the technique to make your own crystals and gems glow.

You can make any clear or translucent crystal glow in the dark! Here’s how I made a genuine quartz crystal glow. You can apply this method to make other natural gemstones, glass, or plastic items glow. If you’d rather grow crystals that glow in the dark, try my glowing alum crystals tutorial. If you want to treat a crystal you already have, read on…

Glow in the Dark Crystal Materials

Technically all you need is a crystal and any phosphorescent paint, but if you want the crystal to glow very brightly, glow for a long time, and resist water and wear, you need three materials.

  • translucent or transparent crystal or gem
  • phosphorescent paint
  • lacquer (acrylic or polyurethane)
  • black light (not essential, but very helpful)

I used acrylic phosphorescent paint by Glow, Inc. and Sculpey glaze, but there are other products out there.

It is important that you choose phosphorescent (which really glows in the dark) and not fluorescent (glows for fractions of a second) paint. Your color choice is somewhat important. Strontium aluminate pigments (the awesome ones) glow most brightly in green and aqua. Blue is quite nice, but a bit darker. Violet and white are beautiful, but not nearly as bright and don’t glow as long. Red and orange are improved versions of zinc sulfide and fade very quickly.

Varathane and Future are good sealant choices. They dry clear and are durable. Clear nail polish is not recommended because it has the reputation of yellowing over time and reacting with some polymers. Some clear polishes may be fine, but the other options don’t cost more, so why risk it?

How To Make the Crystal Glow

The glow treatment on this quartz crystal is invisible under normal light.
The glow treatment on this quartz crystal is invisible under normal light.
  1. If you’re like me and using a pretty crystal you found in the ground, your first step will be to clean the stone and let it dry completely. If you think your stone is already clean, wipe it down anyway, to remove any residue.
  2. Identify the part of the crystal you want to glow. You may be thinking you need to treat the whole crystal in order to make it glow. Nope. You simply need to make part of the stone phosphorescent. What’s important is that this part of the crystal can receive light. For a piece of quartz, rose quartz, pale amethyst, citrine, cubic zirconia, acrylic, etc. this can be any part of the stone. Usually you’ll treat the back of the stone, causing it to appear to glow from within. You could also treat the top and/or bottom of the crystal. It’s up to you.
  3. Use a small paintbrush to apply a thick, even layer of phosphorescent paint to the selected surface. Again, don’t paint the whole crystal unless you want to hide the natural beauty of the stone. You don’t want to do that, right?
  4. Let the paint dry completely. I allowed half an hour.
  5. Apply a second coat. If you have a black light, turn it on so you can see how you’re doing and to identify areas that need more phosphorescent pigment.
  6. Again, let the treatment dry. Now, you should have a nice glow in the dark crystal. Either expose it to black light or else hold it out in the sun or under a bright indoor light or your cellphone flashlight to charge the pigment. Turn out the lights and examine your work.
  7. If you’re pleased with the glow, you can continue to the next step, which is sealing the stone. Otherwise, you may wish to apply another 1-2 coats of paint.
  8. Finally, you should seal the stone. There are 2 reasons for this. The first and most important reason is that modern phosphorescent pigments are destroyed when they come in contact with water. Theoretically pigment in an acrylic paint is already encapsulated and protected, but it’s better to be safe than sorry, or you might have selected a solvent-based paint that won’t protect your pigment at all. The second reason is because the phosphorescent particles need to be large to produce a good glow. This makes the painted surface gritty. Coating the crystal smooths out the surface so the treated area will look and feel natural. Also, I think the lacquer helps prevent chipping and wear of the coating.
  9. Use a paintbrush to apply a thin, even coating of sealant to the treated part of the stone. I stick with one coat and don’t paint the untreated parts of the crystal, but you can coat everything, if that’s your thing. Allow the crystal to dry completely. No touchy! You’ll leave a fingerprint in the sealant, which probably isn’t what you want.

Now comes the fun part. Enjoy your creation! You can leave it on a desk and enjoy its glow whenever the lights go out, place it on a bathroom counter as a night light, or wire-wrap it for a pendant or a keychain.

What are you going to make?