Thread: Lead in Glass
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Old 2007-09-04, 9:55pm
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prairieson prairieson is offline
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Quote:
Originally Posted by Heidi von Frozenfyre View Post
The higher the c.o.e the higher the lead content. The brighter the colors the most likely the higher of c.o.e. and lead

The makers of the glass do not need to say the % of lead content if it's under 39%

If it doesn't have lead it's pyrex.

Lead makes the glass flow.
Hiya toots!

A bit of clarification. More appropriately, the higher the lead content, the higher the coe. While it's true that boro doesn't have lead, neither do many soft glasses. It's the boron that makes it hard glass and soda-lime that makes it soft glass.

To the original question... Renee's post is spot-on, acids can over time cause lead to leach from the glass. But it takes time, it should be fine to drink from lead-crystal but probably not such a good idea to store acidic liquids in it.

While flameworking a bit of lead will gas-off as the glass is melting, but if you've got adequate ventilation and don't "hunker-down" over the torch it shouldn't be a problem. The lead content of the soft-glasses we typically work with is fairly low. As Heidi said, the lead is used to help the glass flow and "fit" with other glasses more readily.

But once our work is ready to be worn or fondled, the lead is safely locked into the glass matrix. There used to be a myth that glass armonica players would die from lead poisoning from constant contact with the lead-crystal bowls in the instrument, but that myth's been since put to rest.

I did see someone working with some neon tubing once, which I suspect had a significantly higher lead content than the soft-glass we use in flameworking, and as the tube was heating about 3 inches of tube on either side of the flame was fumed in silver color... I'm assuming it was lead... yikes!
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