Do the bowls nest?
Snopes would seem to support the OP’s claims. Soda lime glass is, indeed, more susceptible to breakage than borosilicate glass. The soda lime glass has a much higher coefficient of thermal expansion than the more expensive borosilicate glass. When subjected to a rapid change in temperature, the soda lime experiences significant internal stresses and can sometimes violently shatter. The borosilicate glass, since it doesn’t not change in size as much due to its smaller thermal expansion, does not suffer the same stresses. There is a way to tell the difference between the two glasses. Soda lime has a distinctly greenish cast. Borosilicate is much closer to white. Of course, that’s not exactly a helpful test for online purchases.
Every time Woot! Sells Pyrex someone trots out this urban legend. True, Pyrex is no longer owned by Corning. But Pyrex changed over to Soda Lime glass well before the brand was sold.
See the Snopes article already mentioned.
This changeover to soda lime glass happened 60 years ago. (haku: Nope. 60 years ago. You need to try again. Read the article for the facts.)
Or, you can read (the company’s response)[http://www.pyrexware.com/index.asp?pageId=30]. But independent sites like Snopes and Stats.org provide a credible refutation of these urban myths.
But don’t let facts get in the way of a good story. 
ANY glass formulation will break if sufficiently stressed.
Every time Woot! Sells Pyrex someone trots out this urban legend. True, Pyrex is no longer owned by Corning. But Pyrex changed over to Soda Lime glass well before the brand was sold.
See the Snopes article http://www.snopes.com/food/warnings/pyrex.asp already mentioned.
This changeover to soda lime glass happened 60 years ago. (haku: Nope. 60 years ago. You need to try again. Read the article for the facts.)
Or, you can read the company’s response: http://www.pyrexware.com/index.asp?pageId=30. But independent sites like Snopes and Stats.org http://stats.org/stories/2009/exploding_pyrex_oct14_09.html provide a credible refutation of these urban myths.
But don’t let facts get in the way of a good story.
ANY glass formulation will break if sufficiently stressed.
The new stuff lasts forever too, if you use common sense.
people tend to take this to absurd levels. The formula for pyrex was changed over 20 years ago. Most people using pyrex these days are using the new formula. millions upon millions of products sold with only a handful of incidents.
Tempered soda-lime glass is more impact resistant than borosilicate, but not as temperature resistant. That means you should not take it from the oven and drop it in water, take one hot and dry from the oven and pour cold liquid into it, etc. For 99.999% of use, this should never be an issue. If you’re cooking up meth, you may want to get lab grade glass. I have 20 year old new-pyrex oven dishes that I personally have been using for over 10 years in the oven and it’s still here, but I treat it like glass and not like some magical unbreakable material.
Also, all glass cookwear that sold in the US now is tempered soda-lime, regardless of brand.
I also have quite a bit of pyrex glass storage containers. Never had a problem with them, other than one lid (out of very many) that had a split crack in it. Overall it’s really good quality.
You forgot metal counters/stovetops. My mom did that once, luckily she made it to the other side of the kitchen before the thing exploded.
So much for dinner.
BTW, while the vast majority of ovenware is soda lime glass, a quick web search found a place around Pittsburgh that makes borosilicate cookware for private labels, along with lenses and other non-cooking related things.
Other than that… Europe still uses the good stuff.
I heard a saying once, it was something like: Europeans are more tolerant of high prices while Americans are more tolerant of poor quality.
I just bought a set of Lock & Lock glass storage containers from Newegg a couple of weeks ago. It is made with the borosilicate glass. However, it was more expensive than this set.
Yes, they do. I have this set.
I have a similar set from Woot. The glass pieces go great in the dishwasher but I recommend washing the lids by hand.
I love love love this set. The bowls were somewhat redundant of another Pyrex bowl set I already owned, but the fridge lids for the 9" square and 9x13" baking dishes are worth ten times their weight in the aluminum foil I’m no longer using to cover my casseroles. Definitely recommend.
How absurd! “I heard a saying once, it was something like: Europeans are more tolerant of high prices while Americans are more tolerant of poor quality.”
Jaguar and Land Rover, need to buy 2 because one will be in the shop.
Renault - French just suck.
Italy – other than food, they can’t build anything right.
Germany – OK, they have a stellar reputation. I will give you that one.
American’s want quality, but your are right that far too many will take an inferior product over a well made one, because it is cheaper. But don’t blame just American’s, blame the rest of the world sending us their junk. If the US didn’t take this crap, World War III would have happended already. Buy junk for WORLD PEACE! LOL
Not to beat a nit-picky horse, but the 60-year figure is not exactly correct. From the snopes article you implore haku to read: “Sarah Horvath, a Corning spokeswoman, says Corning made Pyrex out of both soda lime and borosilicate at several locations before selling the U.S. business to World Kitchen in 1998, but provided no more details. P. Bruce Adams, formerly an executive scientist at Corning, says that borosilicate was still being used to make Pyrex when he retired in 1987.”
So both formulations were apparently being used in parallel for 40-plus years preceding the sale – and nobody seems to know when World Kitchen may have ceased the manufacture of the borosilicate formulation.
Hey rhmurphy, Facts:
Bottom line: Borosilicate glass (original Pyrex) was made for cooking temperature changes. Boron changes the atomic structure of glass so it stays roughly the same size regardless of its temperature. Little thermal expansion means little stress. Thus borosilicate glass withstands heat.
Soda-lime glass (current Pyrex) has a higher mechanical strength than borosilicate—making it more resistant to breakage when dropped. It is not as heat resistant, leading to an increase in breakage from heat stress.
This from Popular Science:
http://www.popsci.com/science/article/2011-03/gray-matter-cant-take-heat
*“Pyrex, which originally was always borosilicate glass, solved this problem by adding boron to the silica (quartz), the main ingredient in all glass. Boron changes the atomic structure of glass so it stays roughly the same size regardless of its temperature. Little thermal expansion means little stress. Thus borosilicate glass withstands heat not because it’s stronger, but because it doesn’t need to be stronger.”
“When World Kitchen took over the Pyrex brand, it started making more products out of pre-stressed soda-lime glass instead of borosilicate. With pre-stressed, or tempered, glass, the surface is under compression from forces inside the glass. It is stronger than borosilicate glass, but when it’s heated, it still expands as much as ordinary glass does. It doesn’t shatter immediately, because the expansion first acts only to release some of the built-in stress. But only up to a point.”*
Wikipedia reference:
http://en.wikipedia.org/wiki/Pyrex
“Pyrex glass cookware manufactured by World Kitchen is made of tempered soda-lime glass instead of borosilicate. World Kitchen justified this change by stating that soda-lime glass was cheaper to produce; is the most common form of glass used in bakeware in the US; and that it also had higher mechanical strength than borosilicate—making it more resistant to breakage when dropped, which it believed to be the most common cause of breakage in glass bakeware. Unlike borosilicate, it is not as heat resistant, leading to an increase in breakage from heat stress.”5,12,13,14
Seriously, I’m so sick and tired of this endless debate. Everytime Woot sells Pyrex people keep arguing about it. If you dislike the material Pyrex uses to make their containers, DON’T BUY IT! Buy the stuff from Europe or whatever.
Seize the Deal has a much larger set for obviously more money, any thoughts on if it’s worth it? I love Pyrex and have bought at least 4 sets from Woot in the last few months.
http://ww2.seizethedeal.com/deals/pyrex-prep-store-bake-28-piece-set
Just bought the round set recently and ruined the lid in the microwave the first time out. The lid says “microwave” safe, but it is not. It is completely warped and will no longer seal. total bummer.
Buyer Beware
I am a big fan of glass for cooking, eating, drinking, etc. There is always a chance that glass under stress will break. A good tip, however, is that there is a far less chance of breaking an oven-safe glass container if you pre-heat the oven completely before you place the glassware into the oven.
Kind of, but if you stack same-size bowls they will chip around the rims.