Author Topic: This is the only thing I have against Chinese glass!  (Read 1131 times)

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Offline paradisetrader

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Re: This is the only thing I have against Chinese glass!
« Reply #10 on: February 24, 2009, 12:03:29 PM »
Its interesting to note that this seems to happen more frequently or perhaps is more noticable with paperweights than other forms. Interesting also that it's not just Chinese glass it happens with.

In previous discussions it was noticed that yellow colours are often involved when this occurs. I am interested in yellow glass of all shades and have one thick walled item which is oily and rather cloudy.  How might yellow colour(s) tie in with the chemicals mentioned above ?

In yet another discussion, I seem to remember that the development of a very pale yellow colour in pressed glass over time could be associated with an excess of arsenic, ironically, originally used as a clearing agent.

Thanks
Pete

PS Incidentally, I can attest that Leni's home enjoys the benefits of central heating and double glazing which ensures that its warm and not at all damp, despite the English winter.
Pete


Offline Fuhrman Glass

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Re: This is the only thing I have against Chinese glass!
« Reply #11 on: February 24, 2009, 10:54:54 PM »
this problem is not just with the Chinese. I was in a large showroom at a factory in West Virginia a few years ago and all their wares were suffering from this. Lots of stemware and assorted items, not paperweights. I have some paperweights from some American factories that have had this same problem. If the batch isn't right you can have lots of problems. A lot of the European factories have been buying batch from a couple of good sources for a quite a few years and have not been plagued with this problem. Batchmasters were always a very important part of the manufacturing "puzzle".
Many companies don't bother to keep their chemicals stored where they don't absorb moisture, hence when they batch the chemicals and they weigh it out they are off because of the moisture content in the chemicals that they don't calculate for when they are mixing their batch. Some suppliers of chemicals have higher moisture contents than others and can throw off formulations as well.
I heard Dominick Labino lecture on this to a group of studio glass artists about 25 years ago. He emphasized to make "good "glass. He was an extremely good glass chemist.
Tom Fuhrman


 



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