
Fine network of cracks in glass caused by excess alkali in the ingredients. This problem was largely overcome by George ravenscroft in 1676 when he added lead oxide to the metal.
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Fine network of cracks in glass caused by excess alkali in the ingredients. This problem was largely overcome by George ravenscroft in 1676 when he added lead oxide to the metal.
Found on
http://www.encyclo.co.uk/visitor-contributions.php
No exact match found.