Glass, lead
Lead glass
K 20%, O 20%, Pb 1%, Si 9%,

estimated elemental composition and empirical formula weight 
Commercial product likely to contain propriety (non-disclosed) ingredients and additives.

Gram formula weight (molecular mass) = 1561.9
Solubility in organics = insoluble

Glasses contain small quantities of many inorganic materials.
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Lead glass
is defined with respect to the entities below:
The entities below are defined with respect to:
Lead glass
Glass (generic)

chemical compound molecule metal molecular science reaction mechanism ionic material acid base geometry reactivity synthesis science knowledge chemistry Lewis