The original French tumbler, made by the company that invented tempered glass


#1

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#2

I have those in a smaller size and can absolutely recommend them, although that seems a bit expensive. Then again I can see France from my window and that may help with local prices.


#3

Those resemble (but are not identical to) the classic Russian tea glasses, for use in a metal holder.


#4

“They don’t have any real flaws.”…
Until you read the 1-star reviews; they’re amazing!
THEY EXPLODE!!! in one case, on their own, in the cabinet!
Awesome, love it BB; I’m ordering them as gifts for some ‘special’ 'friends.'
Snort / chortle…


#5

They do “explode” instead of cracking, but that’s generally considered a feature and not a bug.


#6

Yeah not so much an explosion as a shattering into those little glass cubes that tempered glass like to do.


#7

Libby manufactured some awesome tempered glasses for a great price, $1 per in bulk buy. I haven’t seen them in restaurant supply stores for a while though. Could be that Libby no longer does tempered glass???


#8

The tempering process adds strength by storing tension in the glass (outer surfaces are in tension against the inside), unlike annealed glass. Once you crack it, the energy’s released and the chunks can fly pretty far. One poorly made tempered glass of mine with a flaw sent shards a good 10 feet - pain to clean. Non-annealed glass can hold a lot of tension.


#9

I’ve got three of the small glasses I inherited from my Mom. They must be near 40 years old none of them ever exploded. I used these Duralex glasses everyday for 20+ years no problem. Friends had a set of Duralex dishes back in the 70’s one plate exploded in the living room covering the table, couch and floor (eating in front of the TV has always had it’s dangers even in the good old days :-). The dogs were also covered with tiny sharp glass shards but the were able to get them outdoors and hosed off without injury. My friend sent them a letter and photos demanding redress and got a thousand dollars from the seller ( a pretty good chunk of money in 1975). It probably helped that she was head of claims dept. for State Farm Insurance Co. But all glass can build up stress when it is manufactured, heated and cooled and cause it to explode, glass blowers go to great lengths to remove that stress by putting their creations thru a range of temperatures in a glass oven to avoid these hazards (not a kiln but a specialized oven). Considering glass is a liquid it is a very scary but cool and beautiful substance.


#10

I don’t know about explosions. These cups last forever.


#11

Bed Bath & Beyond used to carry those, but I haven’t seen them in a while.


#12

I thought these glasses were Hungarian, since that’s where I saw them, in old cafes in the early-mid 90s. Love those things.


#13

One glassware design I’ve looked for and have been unable to find, is the simple hexagonal prism. Lots of octagon and more sided out there, but for some reason the hexes are nowhere to be found… Except for rare thrift store finds. I’d love to amass a collection of six of these.


#14

It’s a bug in my book if it is caused by picking it up.
Or happens in the cupboard.
Or when removing from the dishwasher.

There were more, those are the reviews I read;
read them yourselves.

These may well have once been great, but it sure seems they let a really bad batch out into the market.

Whatever…


#15

You do know that those have been ubiquitous in France for generations, don’t you? It is a non-issue.


#16

Glass isn’t a liquid though. Its a solid. The confusion comes from some eccentricities of old school glass making, and the fact that glass is an amorphous solid. Basically although its a solid, and acts like a solid (as in it can’t flow), its chemical structure remains more similar to that of a liquid.

Temperature changes, and differences in heating through different areas of glass will cause energy/tension to be stored in the chemical structure of the glass molecules. This can make the glass more or less fragile, and when the tension is different across the whole piece of glass is can cause it to spontaneously fracture or explode. The glass makers are using a process called annealing to evenly heat the whole piece to fixed temperatures to make sure it has the properties needed consistently across its entire mass. The same process is used in metal working to ensure an even baseline in the Rockwell hardness before heat treatment.

Tempered glass is different. In this case differential pressure/tension is introduced to the glass in a very controlled manner that strengthens it. But also causes it to break in a very specific way. No large sharp pieces that can cut you, or tiny splinters. Medium sized, rock like, mostly blunt chunks. But because of all that stored tension it tends to break more energetically and completely. Its more annoying to clean up, but its a hell of a lot less dangerous.

Now what people are complaining about is likely the results of thermal shock. ALL glass is subject to thermal shock (pyrex/borosilicate glass is extremely, extremely resilient to it though). Essentially what happens is the piece is deferentially heated. Parts of it are heated more than others, or parts cool faster after heating than others. That brings back the whole tensions/energy being stored differently problem. This is a big part of what glass makers are doing with the autoclaves, preventing thermal shock as the glass cools after its manufacture. Repeated exposure to heat (as during washing, especially in a dish washer) as well as small flaws or damage to the glass increase the likely hood of spontaneous breakage due to thermal shock. Basically you get all that tension in there, and it hits a weak spot and its more likely to go. Often a small shock like a tap, or putting the glass down, or even touching it is enough to make it break. And even non-tempered glass can detonate into those rock like chunks if they’ve been heated and cooled enough.

Being a bartender you deal with glassware A LOT. There’s pretty much a fixed number of times a glass can be washed before it starts to get incredibly fragile. I’ve had stems of wine glasses pop in my finger tips at just a touch. And mixing glasses (often called pints erroneously) are notorious for popping in bartenders hands. We don’t typically used tempered glass, so it can be incredibly dangerous (there are reasons for that). You learn pretty quickly the safest and most controlled way to pick these things up. You never close your hand on a glass tightly. You curl back your fingers in very particular way when tapping the side of stacked glasses to “unlock” them (and you always tap where the glasses are in contact with each other, never where there is a void). Just a few weeks ago I had a pint/mixing glass straight explode when I tried to un-stick it from another glass (I was attempting to teach a server the right way to do it). The top half went like tempered glass, shooting little chunks over 30 feet away (and showering my ice bin, which is one of those reasons I mentioned). The bottom half (in my hand) became a number of very large, very sharp shards. And I ended up sticking myself a few times. Not fun.

Point in the end being that its not at all unusual for glasses of any sort to explode or spontaneously crack. Its just that under home use it takes a lot longer to run it through the dishwasher enough times, or accumulate the sort of damage (invisible or otherwise) that makes the glassware more susceptible. Specialty glass like borosilicate, and presumably tempered, are just more resilient to to temperature. The major down side with tempered glass is that since its already under tension its a lot more susceptible to the sort of minute damage and manufacturing flaws that just weaken other glass. Even with out any thermal shock or temperature shenanigans small chips, scratches, or weak spots in their construction can cause they to simply explode. So its a trade off. The only thing I’ve never seen it happen with is high end lead crystal. But I’m willing to be that has more to do with the fact that these glasses are almost never machine washed. Lower heat for a shorter amount of time should mean less chance of heat damage.


#17

I’d say that the most famous Duralex glasses in France are the ones used in most school cantinas for decades. Small, tough and with a small random number written at the bottom that was an excuse to play game with (smallest number on the table loses, etc.).

And that $30 price for the “Picardie” tumbler is astronomical! Duralex sells 6-pack of 12oz for 12,5€ on their own website and they are 5,99€ on Amazon.fr!


#18

Those glasses are great, it should be the national animal !

You see them everywhere, canteen, bar, houses, and I never see one broke : sometime they even bounce !
There super safe and stackable and I think that’s why there use so much in canteens with children.


#19

The UK schools all used to use them. They said ‘Arcoroc’* on the bottom then. We will probably be using them as money soon.

  • spelling corrected as per comment

#20

That’s ‘Arcoroc’, a tempered glass brand from a different French manufacturer.

(I always associate Duralex with pink mouthwash, as all dentists seemed to use their Gigogne tumblers when I was of an impressionable age).