Back to Ganoksin | FAQ | Contact

Sizing garnet cabochon


#1

i have a calibrated cabochon to replace a lost stone in a pendant.
however it is still slightly too big- if i could somehow take some
of the height of the stone away im sure it would then fit. is sanding
a possibility? regards nikky


#2

Hi Nikky, Yes, done judiciously your can sand down a cab which is too
high. Obviously it works quicker with softer materials like lapis,
turquoise or labradorite; if it’s agate or harder it will take more
time.

I’d use a sanding stick of, say, 220 grit wet-or-dry silicon carbide
glued onto a wooden paint stick or a piece of yardstick. Use it like
a file and keep it wet. Watch you don’t sand a flat spot. 220 grit
would be the first step, for quick removal of material. Then go over
it with 400 grit, and then 800; when the stone has a fine velvety
finish without scratches from the preceding steps polish with any of
the usual polishing compounds; you could probably do that on a
little leather disc in the Foredom. Keep it wet; be careful of heat,
now that you’re using a power tool.

Cheers Hans Durstling in Sunland California - and appreciatively so,
given the temperatures back home.


#3

Nikki, You have lost me a bit. In what way is the cab too big? Height
should not be an issue unless it involves the bezel. In that case,
carefully grind a bit off of the flat bottom, then polish it before
setting. If the circumference is a bit large, again carefully grind
around it and again polish before setting. HTH Teresa