DieForelle
Hazard to Self
Posts: 61
Registered: 2-2-2012
Location: East Coast
Member Is Offline
Mood: No Mood
|
|
warning - possible counterfeit Pyrex on ebay
Pictures:
I bought this Erlenmeyer about a year ago on ebay. It was a company in NJ with good feedback. Most of you probably have no need for such large
sizes of open glassware. I used them occasionally for some experiments with protein hydrolysis.
Just last night I was washing up. Usually I've done this during the day when light enters my kitchen through the windows, diffuse and at an angle.
With the sink spotlight shining straight down, I noticed...BAM...one of these has a green fluorescence and one doesn't. Isn't that a sign that it is
made with soda-lime glass instead of borosilicate? Also, you will note the quality of the logo printing is poor, and the material itself is more
grayish colored with larger "speckles", is washing off more quickly (even though they've only been washed about 10X), and seems less raised. The
funny thing is it hasn't mattered in my experiments because it's only the beaker - which I bought from one of the premiere classroom/educational
suppliers so is probably authentic - that has been subject to temperature stress in my experiments. The Erlenmeyer gets hot and cools down more
slowly.
OK...what do you think? Should I contact ebay's VERO police? JK, probably won't do that. But if you convince it is fake, I will post the ebay
seller's ID.
|
|
|
hissingnoise
International Hazard
Posts: 3940
Registered: 26-12-2002
Member Is Offline
Mood: Pulverulescent!
|
|
That green tint, while suspicious looking may simply mean that there's some contamination by iron!
I would presume cheap borosilicate may not have the highest purity . . .
But if it is indeed soda-lime, it will crack on heating water to boiling on a hotplate!
|
|
|
bahamuth
Hazard to Others
Posts: 384
Registered: 3-11-2009
Location: Norway
Member Is Offline
Mood: Under stimulated
|
|
Well, borosilicate lab glassware all have the same amount of iron in them, well that is the quality ones. The refined quartz we made where I worked
before had to little iron so Duran had to add it to get it leveled with the standard. So if there is green in the glass like your picture I would say
that it is low level glass, but may still be boro 3.3.
Additionally, tempered soda lime glass is almost as strong as boro 3.3, if not better in some cases. Borosilicate 3.3 glassware is used primarily
because its "resistance" to leeching (that is its loss while treated with sulfuric acid and sodium hydroxide) and the thermal expansion properties.
Schott Duran has a very good info flyer on those things with alot of numbers and graphs, as do Wiki.
But have seen the colors blue, red and green on very old boro 3.3, made still while china was in the stone age so not replicas, so don't get to hung
up on the color. But the branding itself is what ticks me off as replica, or it could just be the work of the day, everything is cheapened and
outsourced nowadays compared to the old days when a brand had pride...
VWR has some cheapo boro 3.3 which is slightly greenish IIRC, and those break easier than Schott Duran brand in my experience..
Any sufficiently advanced technology is indistinguishable from magic.
|
|
|
bfesser
Resident Wikipedian
Posts: 2114
Registered: 29-1-2008
Member Is Offline
Mood: No Mood
|
|
I'm not convinced that it's counterfeit. You're comparing to West German glassware... that's just not fair. No other glassware can compare to the
stuff produced in West Germany! Schott Duran comes close in quality, however.
[Edited on 2/2/13 by bfesser]
|
|
|
Hexavalent
International Hazard
Posts: 1564
Registered: 29-12-2011
Location: Wales, UK
Member Is Offline
Mood: Pericyclic
|
|
Not necessarily. From what I understand, soda lime glass often can withstand being heated, just not thermal shock: for instance, a borosilicate test
tube that has been heated over a flame and then immersed into ice water has a greater chance of surviving than a soda-lime one.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
|
|
|
Dr.Bob
International Hazard
Posts: 2753
Registered: 26-1-2011
Location: USA - NC
Member Is Offline
Mood: Mildly disgruntled scientist
|
|
I have used Pyrex for many years. They moved production to Germany years ago, about the same time they closed down their cookware group in the US as
well. I have seen many variations in color and thickness even for glassware in the same lot. I have seen variations in glass from other vendors
as well, Chemglass RBFs of the same size and style can have a 20% or more variation in weight/thickness. And I have seen NMR tubes that are marked
the exact same part number alternate between clear, yellowish and greenish in cast.
But mostly I just don't think that the lab glassware market is big enough to counterfeit Pyrex profitably. There is a much bigger market in DVDs,
watches, and purses, mostly things that have a higher markup.
|
|
|
DieForelle
Hazard to Self
Posts: 61
Registered: 2-2-2012
Location: East Coast
Member Is Offline
Mood: No Mood
|
|
Thanks everyone. Dr. Bob you have a good point about the motives of someone counterfeiting something so obscure. But, in scouring the web looking at
various Kimax, Pyrex, Schott, etc. enameled markings, I've never seen any that look as cheap as this. The way the P is a little too close to the Y
for example. Maybe it's just some Pyrex undisclosed diffusion line, made in a country not as known for its engineering and manufacturing prowess as
Germany.
[Edited on 3-2-2013 by DieForelle]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
