Glass expert needed?

[buzz]

Ok so I recently opened up a retail store! Going great but one of the questions I always get is do you do crystal? I am assuming they are talking about lead glass but not really sure. What is crystal cups or what ever made from is it more expensive then Boro is it more durable? Just want to be able to answer my costumers honestly. Looking forward to your responses.....
Fred

[istandalone24/7]

i think boro is tougher (def is to heat/cold shock) but lead crystal has better optical qualities....but i'm not expert. anyone else?

[Jimi The Don]

lead crystal isn't really used anymore because of well the lead. they substitute different oxides for lead to give it a similar refractive index. it's desirable because of this high refractive index and high dispersion because it looks so brilliant. it can be used to make fake gemstones because of this as well as very "pretty" glassware.

[buzz]

lead crystal isn't really used anymore because of well the lead. they substitute different oxides for lead to give it a similar refractive index. it's desirable because of this high refractive index and high dispersion because it looks so brilliant. it can be used to make fake gemstones because of this as well as very "pretty" glassware.




Is this something that could be worked with a torch and if so where do I get it ? I wanna play!!!!!

[Jimi The Don]

if you wear glasses that are actually made from glass then they are made of "crystal" glass, cuz they need to be invisible in front of your eyes

[Jimi The Don]

it can be worked in a flame, I've never procured it personally but maybe call Shcott and ask them or osram. osram probably does something similar but I'm unaware if they supply small quantities, I've gotten plenty of specialties from them but usually a few thousand pounds at a thyme.

[GatsbyGlass]

I'm quoting directly from Glassblowing by Homer Hoyt - "The term crystal, still in common use today, distinguishes clear glass from colored, translucent, or opaque varieties. As high-lead content glasses became popular for their brilliance, a confusion occurred concerning the use of the word crystal. Finally, modern manufacturers of lead glass products agreed that the term lead crystal should apply only to those items that contain at least 22% lead oxide. So, though the term crystal still means clear, colorless, transparent glass, its composition can vary to a wide degree..."

That was written circa 1989 though, so maybe take it with a grain of salt? It sounds like your customers are probably asking about lead crystal glass, being unaware the term crystal apparently refers to all clear glass. Sounds a lot like the infamous, "do you do double-blown pieces?" question that haunts glassblowers everywhere.

[skip]

I've seen boro silicate marketed as lead free crystal before

[glassnewb]

Lead crystal is all about the optics/refraction and reflection of light. Especially when cut into patterns on the grinding wheel. Crystal is much more fragile that Borosilicate. Most people can not tell the difference visually.

[D. dino i ninjah]

All that Crystal refers to is colorless glass ... way back in the day it was extremely hard to make glass that was colorless or clear.. Lead crystal just means Clear glass with Lead in it .. I have marketed my work as crystal when it is only clear and im trying to sell to snoody people who like the term .. Crystal traditionally in glass just refers to colorless glass .. the boro we use today I believe would likely qualify although you will notice that when cut or snapped the glass still has a slight green tint to it .. I sell crystal hummingbirds .. and I feel like it is a fine description .. because they are clear.. Now Quartz on the other hand that is a totally different ball game ..