Discover here how to cut and shape an onyx stone cabochon.
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Step 1: Materials
For cutting an onyx stone you will obviously need a rough onyx stone and these tools:
A diamond disc saw
A carbide drill
Sandpaper (different grades, from rough to thin)
A jeweler flex shaft motor or similar
A buffing wheel muslin (4 inches) mounted on a bench lather motor
A Polygold 2000 millstone for polishing stones
A metal shaft 3 inches long
Step 2: Cutting the Stone
With the diamond disc saw mounted on a flex shaft motor or similar, start cutting the rough stone above a recipient full of water.
Make sure the stone is always wet to help to cut through and prevent the rock to break for overheating.
Step 3: Shape the Stone
Set the stone on a metal shaft with the help of jeweler wax.
Start shaping the stone following the form you want.
In our case, this is rounded cross shape.
Step 4: Round Shape of the Cabochon
As we want the stone as a cabochon, we have the make the edges.
We glue a sandpaper on a wooden plate and we move manually the stone around until giving it the shape we are looking for.
Step 5: Polishing the Stone
Once we could give the curves to the stone, we can polish it.
First, we use a buffing wheel muslin mounted on a bench lather motor and then a Polygold 2000 millstone mounted on the flex shaft motor.