From: pauld@exploratorium.edu
Date: Thu Dec 26 2002 - 10:31:38 PST
Message-Id: <200212261831.gBQIVbj17701@isaac.exploratorium.edu> From: pauld@exploratorium.edu Subject: Re: pinhole leaded crystal Date: Thu, 26 Dec 2002 10:31:37 US/Pacific
Craig
"Crystal glass" is an oxymoron
in fact glassware that we call "crystal" is not crystalline it is glassy and is
made the same way as ordinary glass.
However it is made as follows according to the NY City college course brochure on
glass.
CRYSTAL GLASS
Preparation:
It is prepared by silica,lead oxide(PbO) potassium carbonate (K2CO3) and
CaCO3.
Properties:
It is heavy glass It is very expensive
Uses :
In decorative glass show piece
The addition of the lead makes the index of refraction of the "leaded" glass
higher.
Paul D
> At Christmas dinner we were talking about the cost difference between leaded
> crystal and "cut glass".
>
> Is the crystal glassware grown in the same way as a turbine blade or silicon
> wafer column?
>
> What does the "leaded" mean?
>
> I understand the industrial applications of crystal growth but this seems a
> bit much for glassware. Not to mention the fact that crystal glassware has
> been around a long time
>
> Thanks in advance!
>
> Craig Childress
> Industrial Technology Instructor
> Hillsdale High School
> (650) 378-8170 x226
> (650) 574-4173 FAX
>
>
>
>
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