I’ve always loved crystal jewelry. Maybe the reason is that my beloved great-aunt gave me a crystal heart on a sterling chain when I was a little girl. Or maybe over the years I’ve realized that jewelry made with colorless stones or beads goes with everything. Whatever the reason, one thing is perfectly clear: many vintage sellers mistakenly describe this type of jewelry. I’ve learned the hard way that all crystal is glass, but not all glass is crystal. What’s the difference? Let me explain what buyers of vintage crystal jewelry need to know.
Is It Crystal or Glass?
If you follow me, you probably know that I am a fan of chicklet necklaces. So when I found these chicklet earrings listed online, I couldn’t resist buying them. As promised by the seller, they have a trio of dangling faceted crystal stones that sparkle when the light hits them.
In contrast are these earrings described online as “Art Deco faceted crystal pendants”. As soon as I was able to examine them, I realized that although the earrings are from the 1920s and Art Deco in style, they are glass, not crystal. While many people use the terms interchangeably, they are not the same material.
Crystal (aka lead crystal) is glass with lead oxide. It is heavier and colder to the touch and has a higher level of refraction than glass. This ability to separate light gives a crystal stone or bead its sparkle. In contrast, the glass earrings shown above are lightweight and flat in appearance.
Vintage Glass Jewelry
I’m not saying that all vintage jewelry made with colorless glass is unworthy – it just needs to be described correctly, so you know what you’re buying. Here are two lovely Art Deco necklaces made with molded glass, one technique used in creating glass stones and beads.
Vintage Crystal Jewelry
Crystal stones and beads can be cut into shapes and faceted. Here are two examples from the boutique.
The crystal pendants in the earrings on the left, shaped like elongated hexagons, are faceted to elevate their sparkle. The stones have flat backs. On the right, the beads in this necklace are faceted and teardrop-shaped (known as briolettes). The center bead is round, and the silver-tone clasp has diamanté accents. The faceting adds to the brilliance of both pieces.
Here is another faceted bead necklace, but it differs from the others. Glass and crystal are both man-made materials, but this piece is a mineral – a gemstone. It is rock crystal, a member of the quartz family, and occurs in nature.
While shopping online for vintage costume jewelry, I am always amazed at the vast number of pieces made with colorless, transparent stones or beads that are described as rock crystal. Somehow, I’m not always sure of the accuracy of these statements.
How Can I Be Sure?
Checking the validity of a claim that a piece is crystal rather than glass is tricky when shopping online versus holding the jewel in your hands. Air bubbles can often be seen when glass is examined under magnification. Faceted crystal has sharper edges than glass, and is heavier and cold to the touch. When holding crystal up to a light source, you can see refraction of light – i.e., a small rainbow.
Rock crystal has this same refraction capability and is harder and more durable than man-made crystal. Because genuine rock crystal is a mineral, its identity can be confirmed with a gem tester that indicates hardness. The quartz group of minerals (which includes rock crystal) ranks 7 (out of 10) on the scale developed by Friedrich Mohs, a German mineralogist, in 1812. Buyers can ask if a piece described as rock crystal has been tested.
The rock crystal necklace and matching earrings shown above came in their original box, which is labeled “Genuine Rock Crystal”. And I’ve used a gem tester to confirm the description.
The Series: True vs. Fake
This story about the pitfalls in buying vintage crystal jewelry is the third installment in my new series aimed at helping buyers become more informed consumers. Read the first two articles: I Was Duped and How to Avoid Tarnishing a Sterling Reputation. And subscribe to my blog, so you won’t miss the next!