6 hours ago, Porthos said:@boilsover I am having trouble finding any information about pre-1998 Pyrex that used soda lime glass. Do you have any links handy for me to peruse?
Handy? No. But I believe it was discussed at length here: https://www.chowhound.com/post/consumer-reports-investigates-exploding-pyrex-751340
Corning had two plants, the epoymous one at Corning, and the other at Charleroi, PA. While the latter has been making Pyrex since the 1930s, the Corning plant is no longer in operation. It's my understanding that the Charleroi plant made both soda lime and borosilicate until the early 1990s, and which time it dropped borosilicate manufacture. This predates World Kitchens license of Pyrex from Corning in 1998. IIRC.
Here's a source, quoting Corning and WK people, that Charleroi has been making soda lime Pyrex for 60 years: http://www.snopes.com/food/warnings/pyrex.asp#BDYHoeyAKzyLdaaE.99
