Who doesn’t love a bit of bling? A little Swarovski crystal can really set off a pendants. And let’s face it, a polymer clay dragon is practically begging to have his magic embellished. So sooner or later new clayers ask the question, can you bake crystals in clay? Yes, usually, you can. But there are several of types of crystals and each one needs to be used a little differently. A related question to baking crystals in polymer clay is baking other sorts of embellishments in clay, such as stones and glass beads, so I’ll address these in this article as well.
Can You Bake Crystals in Clay?
- Polymer clay bakes with low heat in a home oven at 275°F (135°C), this is unlikely to damage most crystals, stones, gems, and rocks.
- Some delicate crystals may discolor, so it’s best to test a small crystal sample before baking a prized specimen.
- Amber, opals, pearls, and some soft stones should never be baked.
- Swarowski crystals and other similar “rhinestones” are glass and therefore perfectly hardy in the oven.
- Beware that some “bling” or crystals are actually plastic and these will melt in the oven.
Can You Bake Crystals in Clay?
The term “crystals” can apply to the “bling” that is also called rhinestones. Or it can apply to natural quartz crystals. I’ll treat each separately and since quartz crystal is a natural stone, I’ll talk about it in that section. The name you’ll hear most commonly used in connection with crystals is “Swarovski”. That’s a brand name of faceted glass gems and beads that is known for its high quality and evidenced by the particularly brilliant light that reflects from them. You can see more examples of Swarovski crystals here. There are other brands of crystals, of course, and you can find them in any craft store. All glass crystals can be baked in polymer clay, though not all shapes and types will give good visual results. Do make sure your crystals are actually glass, though. Plastic crystals will melt. More about that further down.
Most often, clayers are concerned with chatons, which are foil-backed crystals that have a mirror finish applied to the back side. This means that light going into the crystal is reflected back in a very sparkly way. The types of crystals most commonly used are point-backed, flat-backed, and a larger version of the point-backed crystals called a rivoli. The pointed part of point-backed crystals is usually pushed down into the clay. This works well to give depth and reflection to your piece, and it also helps the crystal stay attached to the clay. Flat-backed crystals are flat on the back side and sit on the surface of the clay. All glass crystals can be baked in polymer clay without causing any harm to either the crystals or the polymer clay.
How to Use Crystals in Polymer Clay
How to use Point-Backed Crystals with Polymer Clay
Working with smaller point-backed crystals is amazingly simple. Just push them into the clay, right where you want them in your design, and bake. Most of the time the crystals will stay in place, so if you’re doing a sculpture or something that won’t get much wear and tear, you’re done. But if the piece will be handled, you’ll need to secure the crystals. After baking, once the piece is fully cool, use a fine needle tool or your craft knife and carefully pop the crystal out. It will usually come out easily. Then use a tiny dab of instant glue on the back and put the crystal right back. Loctite Gel and Lisa Pavelka’s Poly Bonder both work nicely. Doing it this way means the fit between the clay and the crystal is perfect and very little glue is required. A lot of people use a dab of liquid clay or Bake and Bond before pushing the crystal into the clay. I found that these were just as easy to remove as the crystals without it. So I just glue after baking.
Another strategy is to push the crystals into the clay, but remove them before baking. After baking, glue them in place.
To use rivolis, if the piece is thick enough, you can use the very same technique as with smaller point-backed crystals embedded into the clay design. But if your piece is thin, or if you need to create a full cup to hold the rivoli, try this. Make a small ball of clay the same approximate size of your rivoli. Make it smooth, flatten it slightly into a thick pancake. Then press the rivoli into the clay pancake. If the edges of the clay splay outward, gently use your fingers to snug the clay around the rivoli. You can the use this clay-rivoli unit in your polymer clay design. Because of the larger surface area, rivolis embedded this way don’t seem to pop out and need glueing.
How to use Flat-Backed Crystals with Polymer Clay
Flat backed crystals can’t really be embedded into the clay very effectively, so you’ll need to attach them with a glue to the clay after baking. Many people use E6000, but others report that it’s messy and often doesn’t cure well. As already mentioned, Loctite Gel works well. So does Crafter’s Pick ‘The Ultimate’.
But a really great way is to use Hotfix crystals. These are flat-backed crystals with a heat-activated glue on the backs, and they’re designed to be ironed onto clothing. But this adhesive works very well with polymer clay. Just press onto the clay with a tiny dab of Bake and Bond, then bake. The glue will activate and the crystals will be permanently bonded.
Have you tried baking with crystals and had them melt or turn brown? Then they’re not glass crystals. Plastic crystals will melt in the oven. They’re also not very sparkly when compared to glass crystals.
Using Un-Mirrored Crystals
If your faceted crystals do not have a mirrored backing, when you embed them into polymer clay the light cannot reflect and it will disappear making the bead look dark and dull. To help this type of crystal reflect light here’s a trick. Go ahead and push the crystal into the clay as usual, then remove it. Now, add a bit of silver leaf or very reflective silver paint to the hole. Now replace the crystal using liquid clay and bake. You could also glue the crystal into the hole after baking.
Baking Plastic Beads with Polymer Clay
Even though polymer clay cures at a fairly low temperature in the oven, it’s hot enough to melt, distort, and discolor plastic crystals and also plastic beads. Before baking, make sure that the beads in question are glass and not plastic. It’s not always easy to tell, by the way. Some plastic beads are quite convincing in their imitation of glass. One way you can tell is to tap them gently against your teeth. Glass beads will have a high-pitched “tink” sound, and plastic beads will be more of a thunk. Another way is to use a craft knife around the bead’s hole or on the back side. If you can scrape the bead, it’s plastic. Glass might scratch, but it won’t scrape off.
Rarely, some plastic beads can withstand the head of the oven. Not sure if yours can? Just try baking them in the oven, by themselves. However, watch them carefully and remove them the minute you see them start to melt. You don’t want a stinky mess! If they can withstand a full bake cycle, then feel safe to use them in your polymer clay creations.
If you absolutely are set on using plastic beads with your polymer clay, you can push them into the clay, remove them for baking, then glue them back into place after baking.
Stones, Glass Beads, and Gemstones in Polymer Clay
Even though these materials are wrought from the fires of blast furnaces and the geologic forces of the planet, new clayers often worry about their durability when baked with a polymer clay project. I think that perhaps there’s more a fear of cracking and shattering than one of the stones or beads melting. Don’t worry, while anything can happen, it’s very rare for beads and stones to crack in the oven’s heat. Have you heard stories of stones exploding when they get hot? I have. And I’ve had it happen in a campfire. Moisture trapped in river stones can cause a rock to explode when it’s rapidly heated. But gemstones don’t typically have moisture trapped inside, and the gentle heating that we use for curing polymer clay is far more likely to dry out a stone than cause it to explode. Although this is for the high heat of metal clay, this chart over at Cool Tools, gives the heat tolerance levels for some common gemstones. This should reassure you that most you’ll use will be just fine in the low heat of polymer clay.
By the way, do you know why glass breaks when it gets hot? When a glass object is created, the outside cools faster than the inside, leading to stresses being captured in the molecular structure of the glass. This is why properly manufactured glass is slowly cooled (annealed) after making to prevent this. But manufacturing defects do occur from time to time and that’s why you hear about Pyrex baking dishes shattering in the oven. If the glass isn’t fully annealed, those stresses will cause the glass to shatter if the glass is damaged, by a scratch or nick, or if the temperature changes rapidly and sharply. Properly annealed glass beads will not crack when baked in the oven.
Heating in the oven can, however, cause some dyed stones to change color. This also happens with some faux pearls and dyed seashells.
To use stones, beads, natural crystals, and gemstones with polymer clay, just add them into your design, nestling the stone into the clay. To make sure the stone or bead stays firmly attached to the clay, do secure the stone or bead in place by using small pieces of clay over part of the stone. A popular style for this involves using tendrils, vines, and small leaves as part of the design that wraps around the stone or bead.
Adding crystals, glass beads, and stones to your polymer clay designs can greatly expand the possibilities of what you can create. You can find lots of interesting stones to use by taking apart vintage and junk jewelry from estate sales. This necklace, created in a workshop with Ann and Karen Mitchell this past spring, was made with only polymer clay, glass beads, some mica powder, and wire and chain. Those large glass beads really make this piece special.
There's more by email!
You’re only seeing part of the fun here on the website. Sign up to get more free polymer clay information, tips, and offers in your email. Directly from me to you.