Is pyrex safe to use on a gas burner?
There seems to be conflicting views on whether a pyrex dish can be used on a gas burner. Can anybody here provide a definitive answer?
Question, why would you want to use a glass dish on the stove? Glass is a horrible conductor and you'd be wasting much of the heat from the burner...
Where do you live? European Pyrex is made from borosilicate glass, the same as in laboratory's equipment; American Pyrex is made from common soda-lime glass.
If you are in America, don't bother trying it at all; soda-lime glass is sensitive to thermal shock. Even though it's tempered for kitchenware, it is nowhere near good enough for the burner.
In Europe, you could take your chances if you have a bowl you don't mind risking. However, there is still a significant chance that it will break on the burner some day. While I think that they use the same raw material for both kitchen dishes and laboratory test tubes (which are obviously OK on a gas burner), kitchen stuff is much thicker. This makes it much more likely to break under thermal expansion.
If you decide to make the experiment with a borosilicate Pyrex, take care to warm it gradually, starting with a small flame, and don't pour cold ingredients into it. Proceed at your own risk. And ask yourself if you really have no pots better suited for the task.
I would be surprised if Pyrex brand is not just plain glass all over the world by now! Even so it is not made of enough purity and casting quality to be compared to lab glass, and lab glass goes bang all too often, so this has got to be an accident waiting to happen. See http://www.consumeraffairs.com/homeowners/pyrex.html
Also, Pyrex brand make ceramic pots safe for use on electric or gas stove top (hob). These should not to confused with their "pyrex" glass line
@TFD, from the German site for Pyrex: "Aus welchem Material ist Pyrex-Glas hergestellt? Pyrex-Glas besteht aus Borosilikat". From http://www.arc-international-cookware.com/de/products/classic/allround-gefaess-mit-deckel, there is a small "faq" tab beneath the second panel. It is confusing that the Pyrex line has products not made from Pyrex(r) glass, but I'm still quite sure that when they tell their customers that their dishes (rated for -40 to +300°C) are borosilicate, I believe them. Of course, they also say not to use them on a burner, which proves that it is a risky idea in itself.
@rumtscho - I'm in Australia. We have both US and European versions, but I think we'll play it safe and assume NO on this occasion. I seem to recall my mother doing something on the stovetop with hers in the 60's, but maybe she just got lucky.
@Bill ditto. And in today's world how can you be sure it's the real deal, and not some clone anyway