[Source] Clear glass cabs

Dear Orchid,

Is there a good source for pre-cut tempered glass cabachons? I have
experimented with alternative materials, ie. resins and acrylic but
need the translucency of glass. I am wanting to place fine objects
beneath the glass and then bezel set with fine silver so the glass
would have to with stand the burnishing. Any advice or
reccomendations for other materials would really help!!!

Thanks to all,

Try using a scratch resistant watch crystal. They are available in
many different shapes, in exact sizes. Many are made of synthetic
sapphire, and will take bezel setting and will wear for a long time.

Good luck!
Christopher Arnett

Hi Pennie,

Tempered glass will be most unlikely to find. Tempering is created
by bringing glass down to 550 degrees F, extremely rapiidly &
holding at that tempurature. At the first aggressive scratch this
type of glass will explode into small pieces. Glass cabochons are
typically fired on a kiln shelf or other flat surface to leave a
flat back & domed top, This shelf media holds heat, disallowing the
tempureing process most likely.

You would probably be best suited using clear glass kiln annealed
cabs, Crystal float 82 COE or Bullseye 90 COE glass, when kiln
annealed is hard enough to withstand most burnishing, softer glass
such as spectrum 96 COE or Italian 104 COE are mostly to soft to
withstand burnishing.

Most craft stores sell the equivilant of melted- flattened clear
marbles for the type of project you are discusssing. They are
actually typically flattened in an oil bath & therefore have a very
smooth finish on the back as well. Kiln fired glass cabs will
usually have a matte type finish on the back related to the shelf
primer or kiln paper, releases that the glass is fired on.

Geosoul arts can provide kiln shelf fired 82 COE or 90 COE clear
glass cabs, in non-calibrated sizes

penny -

pre-cut tempered glass cabachons 

you might consider using clear quartz cabs instead. ‘rock crystal’
(quartz) is very strong and will not shatter, crack, or be scratched
as easily as glass. plus quartz is easier to remove scratches should
you do so while setting them.

opal doublets and triplets are topped with quartz rather than glass
because of these properties.

good luck -

Instead of glass cabs, you could use clear quartz cabs. I do not
know where you would find them, I had someone cut some a long time
ago when I needed them. I have heard of clear quartz cabs for making
opal triplets.

Richard Hart

i have found us plastics to be a great supplier of such things in
acrylic. they are cheap and come in a variety of sizes. us plastics
also has a huge variety of plastic and stainless containers which are
great and cheap as well.

www.usplastics.com if the following link does not work, look under
"sheet, rod, & shapes" specifically product 13324


AlphaSupply is where I purchased my last batch of quartz caps for
ammolite and opal triplets.


These usually have a slight frosted look on the bottom of the cap to
help with the epoxy bond to the ammolite or opal. If you aren’t
planning on using an adhesive simply polish the bottom with some tin
or chrome oxide.