Thread: Lead in Glass
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Old 2007-09-04, 9:13pm
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JetAge Studio JetAge Studio is offline
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Join Date: Apr 19, 2007
Location: Tucson AZ
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Not sure that you have anything to worry about...since Lead Crystal has been around for decades. but...
The concern about lead crystal glass is that certain foods, over a given amount of time and stored in crystal containers (like decanters) can leach the lead out quicker over time. Foods especially acidic, like wine, vinegar, tomato, citrus, etc. leach lead more redily than other "foods". Lead glass is categorized by having a larger amount of lead in it's composition, typically above 25%.
I don't know the percentage of Satake's lead content, but it could be looked into. At any rate, everyday soft glasses the lampworkers, or fusers use is going to be below the 25% range, unless specified. That being said, the glass industry readily uses lead as a flux, so chances are at some point, you're going to be using a glass that has SOME lead in it anyway.

For what it's worth, here's an exerpt from WIKIPEDIA:

"The addition of lead oxide to potash glass also reduces its viscosity, rendering it more fluid than ordinary soda glass above softening temperature (about 600 °C), with a working point of 800 °C. The viscosity of glass varies radically with temperature, but that of lead glass is roughly 100 times less than that of ordinary soda glasses across working temperature ranges (up to 1100 °C). From the glassmaker’s perspective, this results in two practical developments. First, lead glass may be worked at a lower temperature, leading to its use in enamelling, and second, clear vessels may be made free from trapped air bubbles with considerably less difficulty than with ordinary glasses, allowing the manufacture of perfectly clear, flawless objects. When tapped, lead crystal rings, unlike ordinary glasses. Consumers still rely on this property to distinguish it from cheaper glasses. Since the potash ions are bound more tightly in a lead-silica matrix than in a soda-lime glass, the glass when struck absorbs less energy. This causes the glass to oscillate, thereby producing its characteristic sound.[1] Lead also increases the solubility of tin, copper, and antimony, leading to its use in coloured enamels and glazes."

Renee
JetAge Studio
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