Just to"muddy the waters" a little. Mckearin in his book American Glass states that in 1611 Neri wrote in his treatise on glass: stated that glass of lead was known to few but was the fairest and noblest glass of all others at that day made in the furnace. Neri"s Art of Glass was supposedly translated into English in 1662.
I've just been reading Guttery's From Broad Glass to Cut Crystal, The History of the Stourbridge Glass Industry (1956). He talks about Neri's book (translated, BTW, but Christopher Merret) and a couple paragraphs later there's a quote, "Glass of Lead, beyond doubt the
fairest and noblest Glass; if this Glass were as tough as Crystal it would surpass it in beauty...a perticuler sort of Christaline Glasse resembling Rock Christall not formerly exercised or used in this Kingdome" (italics mine). This quotation doesn't have a reference, but strikes me as quite similar to the one Tom talks about, so is it Neri? And what Kingdom? The next sentence in Guttery says, "But glass of lead was not something new; the Lorrainers here had used oxide of lead as a flux in attempts to obtain a more readily fusible mixture when they were forced to cover their pots on the first use of coal as fuel....The technical difficulties which caused Ananias Henzey such troube in Ireland in the sixteen-fifties were probably encountered in attempts to make a successful lead glass." And "W.A. Thorpe, historian of English glass-maiking, asserts very confidently that it was an invention ín the stricter sense of the word, the result of an attempt conceived deliberately and carried out experimentally to provide a sound commercial substitute for rock crystal.'"
...SO, it appears lead was used in a variety of places before Ravenscroft did his thing, but he went down in history for perfecting a high-lead glass.
The Neri bit still confuses me - were they using it in Italy by 1611? It sure would be nice to have that book. Must cost a small fortune.
...I wrote something like this in the Flint Glass thread, but will repeat it here. "The white lead being derived from Flint." Has this been substantiated? It seems unlikely, since flint didn't have much in the way of impurities, it's HARD, and not all that heavy. Would lead have been extracted from it before use, and if not, it seems like it would be hard to control the amount added.
Another quote from Guttery: "At first Ravenscroft had used flints, but the glass which he handed over to English glass-makers when he made no attempt to renew his patent in 1681, was glass of lead." I don't understand why they would be mutually exclusive, doesn't make sense. Flint was just another source of silica. In 1696 John Houghton wrote, "Our glassmen for making the best flint glass use instead of powdered flints a very fine white sand," which could be interpreted as saying that the glassmen used flint still for not-best glass.
Topic: lead glass (Read 110452 times)
