We like drinking out of glass. In many ways, it’s an ideal material for the job. It’s hard-wearing, and inert in most respects. It doesn’t interact with the beverages you put in it, and it’s easy to clean. The only problem is that it’s rather easy to break. Despite its major weakness, glass still reigns supreme over plastic and metal alternatives.
But what if you could make glassware that didn’t break? Surely, that would be a supreme product that would quickly take over the entire market. As it turns out, an East German glassworks developed just that. Only, the product didn’t survive, and we lumber on with easily-shattered glasses to this day. This is the story of Superfest.
Harder, Better, Glasser, Stronger
It all started in the German Democratic Republic in the 1970s; you might know it better as East Germany. The government’s Council of Ministers deemed it important to develop higher-strength glass. Techniques for the chemical strengthening of glass were already known by the 1960s, and work on developing the technology further began in earnest.
These efforts came to fruition in the form of a patent filed on the 8th of August, 1977. It was entitled Verfahren und Vorrichtung Zur Verfestigung Von Glaserzeugnissen Durch Ioenenaustausch—or, translated to English—Process and Apparatus for Strengthening Glassware By Ion Exchange. The patent regarded an industry-ready process, which was intended for use in the production of hollow glass vessels—specifically, drinking glassware.
The researchers understood that glasses typically broke in part due to microscopic cracks in the material, which are introduced in the production process. These microcracks could be mitigated by replacing the sodium ions in the surface of the glass with larger potassium ions. The larger ions thus cause a state of compression in the surface layer. Glass is far more capable of resisting compression rather than tension. The high compressive stresses baked into the material help resist tension forces that occur during impact events, thus making the material far more resistant to breakage.
The process of exchanging sodium ions in the glass with potassium ions was simple enough. The patent outlined a process for raining down a molten potassium salt solution onto the glassware, which would harden the outside surface significantly. This process was chosen for multiple reasons. It was desired to avoid immersing glassware into a huge bath of molten potassium salt, as the large bath of hot material would present safety hazards. There were also concerns that excessive time spent at high temperatures following immersion would lead to a relaxation of the crucial compressive stresses that built up in the glass from the ion exchange. Interior surfaces of the glassware could also be hardened by rotating the glasses on a horizontal axis under the “salt rain” so they were also exposed to the potassium salt to enable the ion exchange.
Recognizing the value of this patent, the Council of Ministers fast-tracked the technology into commerical production at the Sachsenglas Schwepnitz factory. The glassware was originally named CEVERIT, which was a portmanteau of the German words chemisch verfestigt—meaning “chemically solidified.” It also wore the name CV-Glas for the same reason. Production began in earnest in 1980, primarily centered around making beer glasses for hospitality businesses in East German—bars, restaurants, and the like. The glass instantly lived up to its promise, proving far more durable in commercial use. While not completely indestructible, the glasses were lasting ten to fifteen times longer than traditional commercial glassware.
Despite the political environment of the time, there were hopes to expand sales to the West. On the urging of sales representative Eberhard Pook, the glasses were referred to by the name Superfest. The aim was to avoid negative connotations of “chemicals” in the name when it came to drinking glasses. Despite efforts made at multiple trade fairs, however, international interest in the tough glassware was minimal. Speaking to ZEITMagazin in 2020, Pook noted the flat response from potential customers. “We built a wall where we stacked the glasses… Look at it, it’s unbreakable!” says Pook, translated from the original German. “No reaction.” He was told that the material’s strength was also a great weakness from a sales perspective. “At Coca Cola, for example, they said, why should we use a glass that doesn’t break, we make money with our glasses,” he explained. “The dealers understandably said, who would cut off the branch they’re sitting on?”
Production nevertheless continued apace, with 120 million glasses made for the domestic market. Hardened glassware was manufactured in all shapes and sizes, covering everything from vases to tea cups and every size of beer glass. Stock eventually began piling up at the factory, as restaurants and bars simply weren’t ordering more glassware. Their chemically-strengthened glasses were doing exactly what they were supposed to do, and replacements weren’t often necessary.
Regardless, the future was unkind to Superfest. Urban legend says that the reunification of Germany was the beginning of the end, but it’s not entirely true. As covered by ZEITMagazin, the production of Superfest glassware was ended in July 1990 because it simply wasn’t profitable for the company. Production of other glassware continued, but the chemically-hardened line was no more. The patent for the process was allowed to lapse in 1992, and pursued no more.
The question remains why we don’t have chemically-hardened glassware today. The techniques behind Superfest are scarcely different to those used in Gorilla Glass or other chemically-strengthened glasses. The manufacturing process is well-documented, and the world is full of factories that ignore any concept of intellectual property if there was even an issue to begin with. Indeed, a German crowdfunding effort even attempted to replicate the material—only to fall into insolvency this year.
It seems that either nobody can make stronger drinking glasses, or nobody wants to—perhaps because, as Superfest seemed to indicate—there simply isn’t any money in it in the long term. It’s a shame, because the world demands nice things—and that includes beer glasses that last seemingly forever.
Featured image: “Superfest glasses in five sizes” by Michael Ernst
I think nowadays, even though it wouldn’t break much, you could support some continuous production not only from people throwing out or losing theirs, but also from making meaningless design changes that prompt people to re-buy.
I’d like to be able to treat some of my glassware this way… wonder if anyone here has done so?
No one in Germany buys glassware, we use empty mustard glasses for drinking.
With the current Dubai-chocolate thing going one, here is a pro tip: “REWE Feine Welt Pistazien Creme 200g” comes in a wonderful mustard style glass.
Isn’t there something like that going on in US with moonshine in jars?
Jam jars are often straight walled here and makes perfect drinking glasses.
As a new thing? I haven’t heard of it. But, moonshine in “Mason” jars goes back probably as far as moonshine, or at least as far as Mason jars.
A lot of people I have known drink iced tea from Mason jars, almost exclusively.
(“Mason” is a brand of jars typically used for home “canning” and preservation of food. Ball brand makes essentially the same thing, and probably others do as well. I assume Mason and Ball predate the Prohibition era of the 1920’s where moonshine probably gained most of its notoriety.
Yes, it’s weird that we call it “canning” when we “put up” something in a jar, but “jarring” might be, well, jarring. English: I’m perpetually glad that I didn’t have to learn it as a second language.)
To be fair to the trend friendly, I don’t drink alcohol so there could be a super-hot trend that I’m missing…but not missing out on.
“Mason” is a brand of jars…” The status of Mason as a trademark is fuzzy, but today it’s essentially generic. Kerr and Ball both sell ‘mason jars’ and no one cares.
I don’t know if it’s still a thing, but for a while it was common for trendy restaurants to serve water and soda in mason jars.
Canning food in glass jars is just slightly older than using metal cans for the purpose.
Before jars and tins, they used discarded champagne bottles for their ability to resist the pressure caused by the Pasteurization process. They’d fill the bottle up with peas or tiny bits of carrot etc. and press the cork in, then dunk the bottle in boiling water.
Imagine the bother of getting the food out.
What’s with the obsession with mustard things, be it glass or gas?
Heh, nice one. I could add: “No world war without Germany” (election slogan of the German ironic party “Die Partei”). But, when talking to Germans, you know: “Never mention the war” (no, it’s not like that anymore, we became occupier-tolerant).
A more serious background is about recycling:
So far glass is the only material that really gets recycled. Everything else just performs “downcycling”, PET bottles included. So there’s a strong preference for glass containers within those who still care about the recycling issue as such.
As a result, at least as far as I believe, Ikea constructs glassware prices in DE according to mustard jars. Proove me wrong.
Lead in car batteries definitely get recycled.
Aluminum gets recycled in a very real and serious way.
While glass is 100% recyclable, in the US less than 1/3 of glass containers are recycled, where ~60% of aluminum cans are. The International Aluminium Institute reports that the global recycling efficiency rate for aluminum is 76%. Wheras the figures for overall global glass recycling range from 21-36%
I thought Aluminium is the most recycled material, but not sure where I heard that.
Isn’t recycled aluminium indistinguishable from new?
No… not really. Glass is very difficult to separate at the point of collection because glass of different compositions is indistinguishable to the consumers. At best they can drop green, brown and clear bottles in separate bins, if they care enough, but then someone goes and throws in window glass or some decorative bottle that’s made of window glass and ruins the whole thing. There’s no automated way of detecting which fragment of glass has which additives in it, let alone separate them.
So the problem is exactly the same as with plastics: to fully recycle it, you’d have to break it down to its simplest chemical components in a very costly and complicated multi-step reaction – at the temperature of molten glass. It’s far cheaper to just dig up more silica sand and make new glass.
That’s why the glass that does get “recycled” mostly goes into making fiber for fiberglass mats and glass wool insulation. It can’t be made into bottles or windows or camera lenses again because of the mixed content. The fiberglass materials then have their own problems of recycling and are either buried in landfills or ground up back into sand and used for road construction and concrete.
Steel and aluminum are recycled more than glass. They’re easy to clean and separate.
Glass for bottles and drinking are usually not from recycled material since cleaning, testing for bad chemicals, and getting a clear product are more expensive than starting with raw materials. As far as durable glass, I can tell you from a business perspective, restaurant and home glassware is very inexpensive and more durable glassware can be had but is so expensive that it is not worthwhile. Corning has all kind of super durable and impact resistant products but they only go into high end stuff like spacecraft, aircraft, and mobile electronics. Think about how many glasses you actually break at home. In a busy club I would say we went through about one case of glasses a week at a cost of about $25. Not a significant expense even in a high breakage environment.
Mustard and Bratwurst goes well, Mustard and Leberkäs even better. We make movies about that.
https://youtu.be/Y-8bZi2WpIY?t=164
For those without the Knowledge: Leberkäs, (translation Livercheese), has nothing to do with liver and cheese. There is no liver nor cheese. Consistency is more like a Knackwurst formed into a loaf style thing. Cuts are eaten on a roll, with mustard and a big slice of Leberkäs. Typical as a snack between breakfast and dinner. Or all day long.
Ok, granted, it is difficult. If it is called Leberkäs outside Bavaria, there has to be liver in it. Or you call it “bayerischer Leberkäs”, then there is no liver. But “Stuttgarter Leberkäs” always has liver. But still no cheese.
Now what, a_do_z. :-))
add some pepper spray and you get seasoned veterans
its funny but food jars dont seem to break as readily as purpose built drinking glasses do. despite our attempts to make our kitchen fancy, glassware seems to have a lifespan of months and we end up drinking out of prego jars for a couple years before we order new ones.
A German/Trailer Park Boys cultural parallel. I was wondering why my jar of German mustard had a stein handle on it. I was planning to save it, as a matter of fact
This would seen to be a problem with our current economic system. What would we need to change to enable pursuit of superior products like this, rather than wasting resources for the sake of making a relatively few wealthy people increasingly wealthier over selling us the same products repeatedly?
As pointed out in the article, the same technology is used in phone screens. It’s more a case of how much this costs the consumer vs replacing a glass when it breaks. I don’t really break glasses that often so I wouldn’t pay much more for this technology, which I suspect significantly adds to the cost.
Glass is also very recyclable.
Yes, but glass is used often in other products, too, like TVs.
Imagine having a near-unbreakable TV. Would that be worth the cost? As it is right now, one crack on a modern display, and it’s pretty much trash.
What I said above applies to much more than simple glassware, too – after all, not many are becoming wealthy off of selling beer glasses. ;)
I don’t think I’ve seen glass used for TVs since Plasma fell out of favor.
LCD’s are chemically toughened glass. You don’t have any choice when it is big and very thin.
It’s used in phone screens because phones are subject to planned obsolescence in other ways. They can afford to have (relatively) unbreakable screens because the rest of the phone gets phased out by software or by the non-replaceable battery. The point still stands, though. It’d be nice to have an economy that produced durable goods for everyone, even if that meant we didn’t have new things all the time. Unfortunately, it turns out that when you let the average person determine the technological properties of what they want to buy, and run the economy on that principle, they make really bad decisions and evil people get rich by taking advantage of them.
Good point. If my pint glass breaks I’ll be sad for a minute but if my phone screen shattered I’d be sad and out $100’s of dollars. Big difference.
“for the sake of making a relatively few wealthy people increasingly wealthier over selling us the same products repeatedly?”
I have a bad feeling this part wouldn’t change much. A product manufacturer should have some idea how many people re-buy repeatedly due to breakage as well as know number of unique customers.
That will let you math out how much money per unique customer over their life they spend rebuying that product.
That’s going to be the starting price for a single “unbreakable” product going forward, as they aren’t going to choose to make less money, but may very well choose to make the same amount of money all at once instead of spread out over the years.
However in most all other industries, the market has spoken, they don’t want to spend money on something better if they can cheaply get “almost good enough”
At that point maybe we should stop listening when the market speaks.
What i really wonder is …. how much would a glass actually cost to manufacture? Would people actually buy glasses for …. i dunno …. 10 bucks/piece with mediocre design, considering you get really nice ones for less than half the price?
Plenty of people pay 10 per glass of poor designs from retail outlets right now, and these don’t cost that much.
VARDAGEN glasses by that Swedish company? They won´t break. Not expensive.
“We know from all the studies and research we do that people don’t want to buy and throw away things, they want to buy something that lasts,”
Ikea VARDAGEN Glass, clear glass, 15 oz $9.99/6 pack $1.665/glass.
https://www.ikea.com/us/en/p/vardagen-glass-clear-glass-70313106/
There was also ARCOROC or how ever it was spelled, with an ad with stampeding elephants trampling all over it.
The design is, let’s call it “dated”, but I actually like it.
Those glasses are good, but mostly by virtue of being a bit thick. But they will break if you apply yourself. Or drop it on outside on the stone terrace.
Reminds me of the Corell dishes. They call them unbreakable but my mother managed to break so many of them during the 80s and 90s.
Very recently there is a German team of inventors/engineers trying to bring that glass back: https://www.youtube.com/watch?v=XSUHKLeyw4M
No English subs no auto-translation though.
Those are mentioned in the link at almost the end of the article: “Indeed, a German crowdfunding effort even attempted to replicate the material—only to fall into insolvency this year.”
my bad :(
Thanks for sharing. It’s the perfect opportunity to test Android’s Live Caption + translation feature.
Some time ago, I bought some Superfest glasses off ebay. Some of them are in use, but one of them was deliberately dropped from ~0.5m on a parquet floor. My girlfriend is still laughting about my sad face when the glass just shattered in 100000 pieces.
I know that’s not a good test, but I honestly expected more than that :D
The question not asked:
What happens when it does break?
There is a tendency for some treat glass to violently explode when it does finally break. Thus, instead of breaking up into a couple of large pieces, and dozens of fragments it could be thousands of fragments and small shards over a much larger area.
Showering your customers with small shards is worse than smashing a few glasses on the floor.
This is a known problem with gorilla glass too, they can actually make it harder, but most of their work goes into finding a balance. Alternatively, car windshields have been tempered and formulated to shatter into less harmful chunks.
Generally, windshields use safety glass (laminated with a layer of plastic between two sheets of non-tempered glass), but other windows in cars are tempered for the reasons you state.
It explodes.
These and other chemically hardened glassware from other manufacturers had the notorious habit of shattering explosively in the dish washer, especially in the kind of washer used in restaurants and bars that ran hot and fast. Every now and then I remember the whole tray would come out completely sprinkled in tiny cubes and needle-like shards, and you’d have to clean up the entire machine.
OK, that’s really f’d up. I’d rather have glass that behaves in the classical way. I once had a small glass shard (might have been harened ARCOROC now that I think of it) in my foot, nobody believed me it was in there, I got it out, but… yikes.
Another thing that happens with really old hardened glassware is that sodium silicate is soluble in water. The molten sodium treatment that hardens the glass makes the surface partially soluble, which means over time it becomes imperceptibly pitted and corroded, and little bits of glass start to come off the surface.
So if you take a 20-30 year old well-used hardened glass coffee pot and put clean water in it, set it on a stove and watch it boil, at some point you’ll start to see little floaters that kinda glimmer in the light. That’s flakes of glass.
Very healthy to drink.
If there are “flakes”, they’re not soluble – dissolved – in the water.
That sounds more likely to be a result of cavitation.
Ohhh – a few years back may parents got a few all-glass doors installed inside their house.
The one separating the living room from the hallway/stairway got dropped during installation and it sound like a crashing wave or rainshower or something (I was one floor away) – The doors are tough as shit so this one must’ve had a manufacturing defect or got dropped really bad.
For several years after that I kept finding some shards when visiting – eg. when moving the HiFi rack on the other side of the living room or TV/media setup near that door…
Wasn’t an explosion per se but there were no larger chunks/shards either.
i kept reading the comments looking for the one with the word ‘corelle’ and i feel like you checked that box
Check out Tritan glass. Described as a “copolyester” it’s nonetheless indistinguishable from regular glass. I can attest from my former drinks business where we used it on a day to day basis, it is very much less breakable than regular stemware. We lost more of it from when it grew legs and walked away, and rarely from actual breakage.
Even modern Pyrex bakeware is just tempered soda-lime glass rather than the more durable borosilicate glass.
I’m not sure there is much business incentive to glasses that “were lasting ten to fifteen times longer than traditional commercial glassware”. Unless you are a small company trying to make your way into a market with a value add, or you are a big company that can convince customers to pay 10-15 times what they are paying for their glassware.
But even having actual glass that is more durable isn’t as powerful as simply having a branding that consumers associate with durability. Pyrex bakeware frequently explodes when you cook it at 500F, yet people swear by it. I can’t undo the psychological training that advertisers have inflicted on people.
It actually explodes because of the heating or cooling rate, rather than the temperature per se. Glass is actually somewhat poor at conducting heat, so you get huge differences in thermal expansion between the inner and outer layers, which can exceed the material’s stress limits.
Some people know the difference, and look for the original Pyrex in thrift stores. I forget the exact difference, but the logo is different.
Same old story – MBA-type bean counters decide to make something cheaper (but not less expensive), and pass it off as just as good to the consumer. When it breaks, tell the consumer it was their fault.
This happened with InstaPot. They made them too good, meaning their profits weren’t high enough to keep from being bought. The new company made InstaPots looking the same, added features, but the quality was garbage. People got fooled for years by the change.
The company World Kitchen built their entire business on this. It acquired and cheapened Corningware, Pyrex, Chicago Cutlery, Visions, and other quality brands. It even changed its name to Corelle (another brand it bought and cheapened) a few years ago to capitalize on the business goodwill and perceived quality of one of the brands it acquired.
Not quite. World Kitchen was originally the division of Corning that sold all of Corning’s consumer products like Pyrex bakeware and Corningware. It transitioned all of their Pyrex products sold in the US to soda-lime glass when it was still a division of Corning before it was spun out and sold.
It seems like maybe they were trying to license it out to other manufacturers when they should have been trying to sell it directly to restaurant chains. I bet the disruption of cleaning up a glass that breaks is much worse than the cost of replacing it.
They were apparently trying to sell to/through middlemen who liked recurring sales and thought they wouldn’t get them.
It’s hard to buy the market saturation argument when they just got integrated into a country with, what, five times more bars and ten times more restaurants.
That all said, Germany in the early 1990s was a lot less “enchained” than the US, so it’s a real effort to target all of the mom-and-pop restaurants individually and make your money. (Hence the unwillingness of the existing distributors.) But they were overlooking the entire Western Germany full of first-time purchases, IMO.
Duralex still sells glasses advertised as being resistant to breakage. I have dropped them on tile floor and have not shown a scratch. They are made from tempered glass as supposed to thr ion exchange process of Superfest.
Came here to say the same. Duralex are very well-know to Brazilians, as most of us have some glassware from them that is kept in the family since our grandparents. Very durable, usually won’t brake when dropped from the table/sink to hard ground
My parents had just one orphan (not a set) French Duralex glass from 60’s or 70’s and still alive but a little faded surface. I inherited it. Strong like my IKEA Vardagen glasses from 2018. Many times dropped, not yet broken.
I recently bought a countertop reverse osmosis unit. It has a glass carafe with a plastic lid. I accidentally dropped the carafe onto the kitchen floor, from about four feet. It bounced three times, but didn’t break. The plastic lid shattered, though.
The lid has a float in it, so an optical sensor knows when the carafe is full. Thankfully, I could order a lid as a spare part.
I made the mistake of looking at asking prices on e bay…
Back in the Sixties there were TV ads for drinking cups that wouldn’t break- they showed one being used to drive a nail! They also showed hose that wouldn’t run, and a vacuum cleaner that was quiet and would still pick up well… Oh, for a time machine!
Legends say that vacuum cleaners are loud on purpose to convince a user that they’re doing a good job – especially tuned for the little clattering sound when sucking up big chunks.
The process of replacing sodium ions in glass surface with potassium ions has been known for some time. If memory serves, a student developed such a process for treating eyeglasses back in the 70s, except that their process involved dipping the lens in a molten potassium salt. It won them a major award (no, not the “A Christmas Story” MAJOR AWARD :-D) in the International Science and Engineering fair.
I´ve not seen this linked in the comments, so here I go (first HAD-post, yay!)
There is someone trying to recreate the old unbreakable glas (or even make normal glas unbrakable):
https://www.youtube.com/watch?v=XSUHKLeyw4M
Best,
eVel
Forget transparent aluminum. Use unbreakable glass instead!