
The Pyrex Glass Controversy That Won't Die - curtis
https://gizmodo.com/the-pyrex-glass-controversy-that-just-wont-die-1833040962
======
supernova87a
It happens to a lot of brands. Private equity investors sniff out a name brand
that has a lot of customer trust, but management that's probably weak after
years of profit and not paying attention. They buy out the company and strip
out all the costly materials, fire staff, sell off inventory.

The brand changes, but customers don't know it until your Breyer's ice cream
has a label that says it's "frozen dairy dessert product", or your Twinkies
are 10% smaller, or your Pyrex glass pans start shattering. Then you wonder
what happened to your beloved childhood / family brand you trusted.

Capitalism is what happened. But things come and go, and hopefully newer,
better things will take their place.

(By the way, the story of what happened to Twinkies is more interesting, and
not just the negative story of a company cheapening out its product for
profit's sake. There was a lot of dysfunction/waste in that product line.)

~~~
walrus01
This is basically what happened to Tim Hortons in Canada. They used to
actually bake things on site, now it's all reheated from frozen deliveries of
sub-par donuts and baked products.

It's been riding on patriotism and brand loyalty for 15+ years now.

~~~
rpeden
At this point, though, I don't know many people who go there out of patriotism
or brand loyalty.

They mostly go there because it's convenient and it's cheap enough, and
quality is usually acceptable given the price. I sometimes get coffee there
not because I'm expecting something great, but because I need a quick infusion
of caffeine-containing liquid and Tim's is 10 meters from my front door while
everything else is further.

In my mind, Tim Hortons is all about location. They're everywhere. And even if
the quality is mediocre, at least it's consistently mediocre so I know what
I'm getting. :)

------
colanderman
Protip: You can tell soda-lime from borosilicate by using a homemade
polarimeter. [1] Get a pair of polarizing sunglasses, and hold them in front
of a computer monitor at such an angle that the screen looks black. Hold the
cookware in between the glasses and the screen. You should now be able to see
the screen (see my synchronicitous comment [2] yesterday about the link here
to quantum mechanics). If you see a checkerboard pattern, you are holding
tempered soda-lime. (The pattern is due to the tempering process.)

Soda-lime also has a distinctive greenish tinge when viewed edgewise.
Borosilicate is clear.

[1]
[https://arstechnica.com/civis/viewtopic.php?p=2746878#p27468...](https://arstechnica.com/civis/viewtopic.php?p=2746878#p2746878)

[2]
[https://news.ycombinator.com/item?id=19406122](https://news.ycombinator.com/item?id=19406122)

~~~
jrootabega
That's wild, thanks! I tried with a couple of my pieces (although they do say
"not polarimeter safe") and they did have some noticeable brightness
gradients, though I hesitate to call them patterns.

What DID stand out looked like brown scorch marks or stellar jets/magnetic
poles. I don't think they were really scorch marks, but it was striking just
how brown that tiny area was.

Edit: got a picture but it's more of a red and blue interplay than just brown.

[http://imgur.com/a/0xRlg9D](http://imgur.com/a/0xRlg9D)

Maybe it's the rgb of the monitor. And I have seen similar colors in
windshield polarization. It makes more sense if you rotate the glasses and
watch the brown and blue flow through the patterns

~~~
colanderman
That's definitely soda-lime. (Judging both by the pattern and the logo.) The
reason for that pattern according to the source I linked above is that that is
the shape of the air jets used for cooling the glass during tempering.
Windshield glass shows the same patterns for the same reasons.

------
evan_
> Corning employee Jessie Littleton discovered a new use for the material
> after his wife Bessie used a sawed-off borosilicate glass battery jar for
> baking.

Sounds more like Bessie discovered the new use, not Jessie.

EDIT: The Corning Museum of Glass credits them both- while noting that it was
Jesse’s idea to try it.

[https://pyrex.cmog.org/content/littletons](https://pyrex.cmog.org/content/littletons)

Incidentally the Corning Museum of Glass has an a YouTube channel worth
checking out. They have a bunch of long, well-shot glass artists doing some
incredible work, start to finish- good videos to play in the background while
working on other things.

~~~
ChrisFoster
I second that, the CMOG channel is great. They have high production quality
(especially consider the constraints of the glass shop) and really talented
artists / craftspeople.

Bill Gudenrath's series on Venetian glassware is particularly fun because he's
such a craftsman but also a fascinating teacher.

------
NeedMoreTea
If you want _proper_ Pyrex, just go to ebay or a European site, and find
British (second hand) or French Pyrex.

It's all still borosilicate glass. Helpfully the brand logos are slightly
different for the different countries, so it should be easy to spot.

It seems daft to me to take away the main selling point of the stuff by
starting to make it with cheap glass.

EDIT: Infographic with dates and the different logos:
[http://www.biggreenpurse.com/wp-
content/uploads/2016/01/Pyre...](http://www.biggreenpurse.com/wp-
content/uploads/2016/01/Pyrex-infographic_optimized.png)

~~~
crocigator
If you want proper borosilicate glass, just go to a company that has been
honest with their branding.

I've found SIMAX ([https://www.kavalier.cz/en/simax-
home.html](https://www.kavalier.cz/en/simax-home.html)) to be a good one
personally. Made in the Czech Republic by a glass company that still makes
labware, and as best I can tell, _everything_ they make out of glass is
borosilicate. Even the flower vases.

~~~
omnimus
How can you tell? It says made in czech rep but nothing about type of glass.

~~~
phonon
[https://www.kavalier.cz/en/simax-professional/simax-
glass.ht...](https://www.kavalier.cz/en/simax-professional/simax-glass.html)

"Simax glass ranks among the types of glass of the group of clear „hard“
borosilicate glass „3.3“, which excel in a high heat and chemical resistance
and which are defined by international ČSN ISO 3585 Standard. It complies to
the full with the properties prescribed by these standards."

------
Treblemaker
"Based on reports made to the company and the Consumer Product Safety
Commission, less than one tenth of one percent of the millions of Pyrex
products sold each year experience thermal breakage"

So, that's potentially thousands of people experiencing this each year? Not a
record I would be proud of....

~~~
CamperBob2
Also, how many people bother to report a broken baking dish or whatever?
Figure the reality is at least 10x worse.

~~~
calciphus
This is my small batch, artisanal data: As an avid baker and engineer, over
the last decade I've had two pieces of cast iron catastrophically fail vs one
piece of borosilicate. I'm not sure if that makes metal twice as dangerous, or
if people maybe report things breaking disproportionately to the manufactured
volume...

I will say feeding my future father in law a glass casarole was not a strong
move.

~~~
Xcelerate
> I've had two pieces of cast iron catastrophically fail

How does cast iron fail? Was this like a cast iron pan or an enameled dutch
oven?

~~~
geggam
Cheap cast has impurities causing expansion rate differences. Cast being
brittle will cause that to pop. Also one of the reasons brazing cast is not
straightforward

------
pjungwir
Oh interesting. We've lost several pyrex dishes. The first was nine or ten
years ago. My wife was baking a raspberry crisp thing (or some red fruit), and
the dish cracked into hundreds of little bits before we took it out of the
oven. Each bit had sides maybe half a centimeter long. It certainly wasn't
caused by a drastic temperature change, unless you count opening the oven. It
is very unnerving for your dessert to turn into shards of broken glass. I hope
this article gets a wide audience, and business goes to a more deserving
company.

~~~
pixl97
The glass probably had a scratch at a stress point. It doesn't take much for a
slight thermal shock for it to explosively decompose at that point.

~~~
samhain
Oh, so maybe these people are using knives to cut things out of the pans,
which causes the initial cracks in the glass.

------
PorterDuff
Thanks for the article. I was looking to replace a chipped old Pyrex measuring
cup about a month ago and found myself going down this same rathole of
research.

It all makes perfect sense as I just naturally assume that all old-school US
consumer goods go through the same sequence of events:

1) sell the company, close US factory 2) license the name to a manufacturer in
China 3) cost reduce, cost reduce, cost reduce 4) profit!

You could make a good BOLTR-like youtube channel by weighing and measuring
changes over time in common products. The KitchenAid mixer would be a good
one.

~~~
gh02t
AvE has one video on the KitchenAid, if I recall correctly he was actually
surprised that it was still pretty well-built.

[https://www.youtube.com/watch?v=0qKp-0h9P18](https://www.youtube.com/watch?v=0qKp-0h9P18)

~~~
pfranz
In the early 2000s there was a lot of talk about KitchenAid switching to
plastic gear housings. They switched back after a few years either due to
backlash or warranty issues.

Here's a cool comparison of wahl hair clippers from 50 years ago and a modern
pair:

[http://grathio.com/2016/08/teardown-same-product-fifty-
years...](http://grathio.com/2016/08/teardown-same-product-fifty-years-apart/)

~~~
sokoloff
> due to _backlash_ or warranty issues.

I see what you did there. I suspect it was unintentional, but it’s quite
pleasing nonetheless.

------
PhantomGremlin
Wishful thinking in the article. They say:

 _Amazon Basics sells a pair of borosilicate glass pans for $15._

But _clicking_ on the link to those glass pans finds review comments like
this:

"These are not borosilicate"

"glass will crack after minimal use"

"Broke first use"

I've never bought an AmazonBasics product, and I don't think I'm going to
start any time soon. In my mind Amazon now stands for "cheap" and
"counterfeit". Not a brand name I want to trust any more.

~~~
jrootabega
The internet is about 50/50 lying companies and idiot users. Amazon likes to
consolidate reviews for different products, versions, and sellers together,
which makes it impossible to know what you're gonna get without actually
ordering it.

------
propter_hoc
It's true that borosilicate Pyrex is better than the newer stuff, but honestly
both are inferior to stoneware, cast iron or stainless steel. You will not
find any professional kitchen cooking in glassware.

~~~
devit
Borosilicate glass (and some aluminosilicate glass-ceramic) is transparent,
doesn't leech iron or nickel into the food, is easier to clean since limescale
doesn't bind easily to it, doesn't rust when exposed to salty water, can be
used in a microwave oven, unlike cast iron and stainless steel.

The only disadvantage is that it shatters if you drop it or hit it with enough
force.

~~~
philwelch
Iron is a nutrient, though.

~~~
code_duck
Indeed, and cast iron pans are specifically employed by vegans for the dietary
iron they provide.

------
tomohawk
Yet another casualty of moving production to China. I knew one of the Corning
execs who headed up moving everything to China and setting up the factories
over there.

At the time, regulatory costs in US were crazy, so plenty of motivation. For
example, if an accident occurred in a single factory, OSHA would make all
Corning employees everywhere go through training about it, even though the
accident involved equipment and processes that only existed at the one plant.

------
MagicPropmaker
This is very timely because I had a Pyrex-type glass lid explode on me today.
It was a lid to a Calphalon frying pan,and I was grilling a veggie burger and
some onions. I put the lid on and set told Alexa to remind me in 2 minutes.

Just before the alarm sounded: "BOOM" and there were a thousand little pieces
of glass everywhere.

I've had this happen when I've heated it unevenly, or when I accidentally put
cold water on a hot container, but never in normal use.

I'm wondering if Pyrex hasn't changed, but if cook tops have. Are they hotter
or less even than cook tops of the past?

~~~
makomk
Pyrex has definitely changed, in the US at least. Pyrex-branded cookware is no
longer made out of Pyrex (borosilicate glass). Which is particularly shameless
because the whole reason for Pyrex is that ordinary soda-lime glass, which
they're making it from now, isn't suitable for this purpose because its high
coefficient of thermal expansion makes it shatter.

------
pfdietz
The lawsuit against those researchers was particularly shameless, in my
opinion. Will avoid products from this company in the future.

------
Reason077
My brother once cut his hand badly when an IKEA glass shattered in his hand
while washing it. (Either he was washing a cold glass in hot water, or a hot
glass in cold - I forget which).

It resulted in a trip to the hospital for stitches and his still has the scar.

I think they've improved these days, but there was a period where certain IKEA
glasswear was very prone to thermal shock.

~~~
fraudsyndrome
I've had this happen to a friend except it was stacked on top of each other.
Trying to pull it apart when stuck ended up breaking the glass with the shard
going into their hand.

------
toyg
The link to safety instructions goes to a geofenced 404 for me in UK. Who puts
safety instructions behind a geofence? Somebody scared of European consumer
laws, that’s who. Not a good look...

~~~
benj111
The European product is different to the American product, so it does make
_some_ sense.

------
msds
John C. Mauro does some really cool work, if you're interested in the
underlying statistic mechanics of glass, and how to use computers to design
better glass.

------
geggam
I was doing the melt pepto bismol into bismuth experiment and using a rosebud
oxy acetylene tip and found some of the soda lime kind. Also demonstrated why
safety glasses are important.

That much temperature caused a pretty good boom with shrapnel when the glass
exploded

------
e40
More interesting to me is the same issue with CorningWare[1]. I've used this
for microwaving food for decades and I've bought a lot of it off ebay. In
fact, that's all I've used ebay for in the last 10+ years. According to the
wikipedia page, it suffers from the same borosilicate vs soda-lime issue.

[1]
[https://en.wikipedia.org/wiki/CorningWare](https://en.wikipedia.org/wiki/CorningWare)

~~~
shawnz
Corning is one of the companies they are discussing in the article

------
based2
[https://en.wikipedia.org/wiki/Planned_obsolescence](https://en.wikipedia.org/wiki/Planned_obsolescence)

[https://www.activesustainability.com/sustainable-
development...](https://www.activesustainability.com/sustainable-
development/battle-against-planned-obsolescence/)

------
ars
Is it possible to buy new aluminosilicate glass dishware commercially?

For some reason I really want to try cooking directly over a flame with a
glass pot.

~~~
nate_meurer
No you don't. Glass is nearly the worst possible material for stovetop
cooking. With thermal conductivity roughly 1/70 that of cast iron, it's
impossible to cook on a range without burning the food, and that combined with
a relatively low heat capacity makes it useless even for searing. On top of
that, glass seems to be a uniquely sticky cooking surface. It's far stickier
than unseasoned steel or aluminum.

I have several pieces of Visions. I would never, ever use them on a range. I
use them exclusively in the oven, where the IR transmittance of the glass is
useful, and the uniform surrounding temperature makes the poor thermal
conductivity a non-issue.

~~~
dasil003
How does lower thermal connectivity cause the food to burn easier?

FWIW, when I was a kid we had pyrex bowls with clip-on handles for stovetop
heating. Yes, you wouldn't cook with it, but great for re-heating food.

~~~
baddox
Presumably it causes food to burn easier because the areas directly touching
the flame/heating element become the temperature of the heating element,
rather than spreading the heat out across the surface of the container.

~~~
dasil003
Yeah that makes some sense, but I'm skeptical. Like the sibling comment here,
I have glassblowing experience and intuitively since glass changes temperature
more slowly it is naturally less prone to hot spots. Also, it is generally
thicker than most metal cookware which means more distance between the heating
element and the food to disperse the head. Speaking from experience, touching
a 250°C oven heating element will generally burn you worse than touching 600°C
borosilicate glass, strong spinal reflex from the former notwithstanding.

~~~
nate_meurer
> _...intuitively since glass changes temperature more slowly it is naturally
> less prone to hot spots._

You've got it backwards. This is a well-known principle in cookware
construction, and it's the whole reason that copper and aluminum clad cookware
exists. Al and Cu spread heat more quickly, and thus farther across the pan
body before it's conducted or radiated away. Remember that the heat isn't just
building up in the pan forever; it's dissipated nearly as fast as it's
supplied. The heat is conducted to the food in the pan, and in the case of
glass it's also being quickly radiated away due to the material's high
emissivity and transparence to IR at low-single-micron wavelengths. Thicker
glass is generally even worse just because it takes so long to heat up, so the
parts that are farther from the flame never reach cooking temperature, while
the closer parts are scorching hot.

Look up any review of cookware where they use thermal imaging, and you'll the
see the results of thermal conductivity on heating evenness. A pan that uses a
lot of aluminum or copper will have a much more evenly heated surface than a
pan made only of cast iron or steel. And glass is a hundred times worse yet.

~~~
baddox
I don’t have much experience with cooking, but this sounds correct to me from
what I know about thermodynamics. After all, air has much less thermal
conductivity than glass, but if you stick a potato over an open flame you
expect a spot on the potato to burn, rather than all the air to slowly heat up
and heat the potato evenly.

~~~
nate_meurer
In fluids like air, heat transfer is dominated by fluid flow, in the form of
convection in the case of cooking over an open fire.

It's useful to think of a piece of cookware as a kind of radiator, because
that's essentially what it is. Heat is transferred to food by direct contact,
but also by radiation. Pots and pans are shaped perfectly to maximize both
radiation and conduction by contact, and thus they experience a very high rate
of cooling. This means that if you want evenness of heating, then high thermal
conductivity is necessary in order to keep up with the heat loss.

------
Causality1
Frankly you could go through life assuming any company that sues for
"defamation" is the bad guy and me right 95% of the time.

------
phasetransition
Reminds me of an experiment in my undergraduate glass lab. Take soda-lime
stirring rods and break 50 or so under 4 point bend test. Record strength.

Take another batch and simply log-roll them along the lab bench for half a
meter. Repeat break test. Note the reduction in strength signficant at p=0.05
.

Fracture toughness is a bear.

------
ecopoesis
The “pleasing heft” the article mentions is a sign that you have soda-lime
glass instead of borosilicate. A few years ago after having a 2-cup soda-lime
Pyrex measuring cup explode I order the equivalent from Arcuisine in
borosilicate and I was amazed at how much lighter it was.

------
sitkack
That sucks, I bought Pyrex specifically because I thought it was borosilicate.
Never another Pyrex for me. I assume my Pyrex labware is ok.

------
robertAngst
>parent company of Pyrex among others, is planning to merge with Instant
Brands, maker of the very popular Instant Pot.

Talk about a highly advertised product.

Before Instant Brands starts spamming 'Mom posts', about how great Pyrex is,
expect it to be heavy and burn your hands if it gets hot. My tupperware isnt
like this.

~~~
code_duck
Advantage I see for glass is that it’s rather inert, so you never have to
worry about BPA or whatever else leaching into your foods, or it catching on
fire or melting. Harder to abrade Pericles into your food.

Also, glass can be scrubbed entirely clean, unlike plastic. When I was
diagnosed with celiac disease, I had to throw away most of my dishes that were
not glass or metal.

Disadvantages of glass clearly include fragility.

