The Low Down on Crystal, Part 4

How Can I Tell if It’s Glass or Lead Crystal?
Part 4 of 5 part series on understanding crystal as a material

There are kits you can buy that can test for lead content. However, there are ways to guess without such a to-do:

By sight: Just by looking you should be able to distinguish. The lead in crystal makes it incredibly clear and gives it a tell-tale rainbow spectrum sheen; when you turn a piece of crystal about in the light, small glimmers of color appear. Glass will not have that rainbow sparkle or the simple clarity of crystal.

By touch: Another way is to feel the weight of the piece of crystal in your hand. Crystal is noticeably heavier than glass. You might not expect it, but intuitively, you probably have a good sense for how heavy glass should feel—think about how many glass jars, bottles, and cups have you held in your lifetime. So, you should be able to gauge if that amount of material in your hand weighs as much as, or more than, what that amount of glass would weigh.

By sound: This is mostly a trick for glassware, since small crystal beads don’t make a strong sound when you tap at them, but this would likely work for larger, thinner pieces of chandelier crystal or glass. Just give it a flick with your finger or tap it with something—if it is crystal, the noise it should make is a reverberating and clear “clink” or “ting.” If you end up with a thudding noise, or really a “tunk” that does not reverberate, then you are holding glass.

By very fun destruction: Also, crystal is more durable and does not fracture into as many pieces as glass, so if you have an extra piece to smash up, this could be a good test to see how it breaks. If it breaks into 2 or 3 clean pieces, then it’s probably crystal, but if it shatters into several pieces and small shards then it’s most likely glass.

If all else fails and you really cannot figure it out (i.e. if you’re blind, deaf and armless), then you should go ahead and purchase a lead-detection kit (and have someone with appropriate physical means help you with the process). Kits come pretty cheap, I’ve seen some for about $13.00, so if you want a definitive answer there is that option.

The Low Down on Crystals, Part 1

What is Crystal Made of?
Part 1 of 5 Part Series on Understanding Crystals as a Material

So what is a crystal really? Well, that’s tricky to answer. It’s clear when trying to purchase pieces for chandeliers or jewelry making, the quality can vary greatly based on the composition, the cut, and the country of origin of the piece of crystal. I’ve learned some interesting facts about crystals from my mother, who has been designing chandeliers for some time now—and she has worked with just about every type of crystal imaginable—and also from my own meanderings into jewelry making and buying beads to that end.

Conservatively, we say that only a bead which has at least 24% lead content is labeled crystal (also called “full-lead” crystal). However, in America the rules are more lenient, and any optically clear glass can be called crystal even though there is 0% lead content. There are even American manufacturers of acrylic crystal (high-quality plastic—not something I would put on a chandelier…).

Here’s another way of categorization, by an American crystal company:

“Crystal falls into the 3 main categories. Fine Crystal or Crystalline is made from a glass mixture that contains 6% - 10% lead oxide. Lead Crystal is made from a glass mixture that contains 10% - 24% lead oxide and Full Lead Crystal is made from a glass mixture that contains 24% lead oxide or more.”

Some manufacturers go above and beyond that 24% mark. High quality crystal usually has about 30% lead content, but the best of the best can get up to 70% lead content, the fois gras of crystals being Swarovski Austrian Crystals (all have at least 32% percent, except for a special line of lead-free crystals they produce). Fun fact: Swarovski’s brand of chandelier crystal, Strass, provides the crystals in the chandeliers at the Metropolitan Opera in New York City as well as the Chateaux at Versailles, Paris. If it’s hanging in a world-class setting, the chandelier is clothed in Strass crystals.

But wait, did you say lead? (Part 2)

Sources:
Personal Experience
http://www.cristalier.com

http://www.chandelierparts.com/aboutourcrystal.aspx