So, how can you actually tell if you’re dealing with “real” Pyrex? As a rule of thumb, it’s safe to simply assume you aren’t—at least, not if you’re in the United States. The “real stuff” hasn’t existed at all in the U.S. market for at least 30 years. Pyrex started phasing out borosilicate glass in the 1950s and had stopped using it entirely by 1998, when World Kitchen (now Corelle Brands) bought the license to the PYREX and pyrex brands. Unless you buy your cookware from a vintage shop that can prove it was manufactured in the 1940s or earlier, you’re very unlikely to come across borosilicate glass pyrex.
You can also tell by looking at the glass. If you look at an edge, you should be able to see the color of the glass and it will either see yellow or a blue.
Yellow is soda glass, blue is borosilicate.
Also, the superfest glass still exists, but is not used for the same applications. A variation of it is used in the production of glass used in electronics such as phones and tablets. Its not every brand, but I believe Gorilla glass uses a similar procedure.
Yeah although the dates surprise me. I thought I had borosilicate Pyrex from the 60s or 70s. Anyway, sucks that it isnt made any more, it is tough stuff.
Last I heard, there were two Pyrex’s in production, and you could tell the good from the bad by subtle differences in branding.
Edit to add: https://lifehacker.com/that-viral-pyrex-brand-hack-is-horseshit-folks-1850157381
You can also tell by looking at the glass. If you look at an edge, you should be able to see the color of the glass and it will either see yellow or a blue.
Yellow is soda glass, blue is borosilicate.
Also, the superfest glass still exists, but is not used for the same applications. A variation of it is used in the production of glass used in electronics such as phones and tablets. Its not every brand, but I believe Gorilla glass uses a similar procedure.
I believe France still makes Pyrex with the borsillicate instead of soda glass but every other plant uses soda glass
Yeah although the dates surprise me. I thought I had borosilicate Pyrex from the 60s or 70s. Anyway, sucks that it isnt made any more, it is tough stuff.
You can still find similar products if you shop online specifically for borosilicate, but they won’t necessarily be from Pyrex. For instance, OXO has a good reputation: https://www.oxo.com/oxo-gg-2-cup-glass-measuring-cup.html