Post by bobby1 on Apr 2, 2010 23:07:44 GMT -5
Last weekend my wife and I went to some gem and mineral shows and at one I found this large Brazilian (Parana) Agate slab. It was destined to be a large cab. When I was looking at the slab my wife and I differed on which side should be the front of the cab. A compromise was reached and it was decided to make a double cabochon so either or both sides would be the front. This is one side backlit. It is my favorite side.
Her favorite side backlit.
My favorite side frontlit.
Her favorite side frontlit.
Here are photos with the proposed cab outlined on the slab.
Here is the preform trimmed to the outline.
Unfortunately the slab had been cut on an angle so the sides weren't parallel.
I scribed an outline on the girdle and trimmed the slab on my 8" trim saw (took about 20 minutes of trimming) until both sides were closer to being parallel.
Next I scribed a center line on the preform and two lines on either side to use as guidelines for grinding the domes on each side.
These next two photos show the (almost) completed cab. Unfortunately there was a small fracture in the clear opening of the pattern on the bottom that propagated to about 1" long as I was working the cab.
I subjected the fracture to an Opticon treatment and it significantly sealed it.
The completed cab. It is 4-1/2" across and destined for my display case.
Here is a photo of the side showing the double dome of the cab.
Bob
Her favorite side backlit.
My favorite side frontlit.
Her favorite side frontlit.
Here are photos with the proposed cab outlined on the slab.
Here is the preform trimmed to the outline.
Unfortunately the slab had been cut on an angle so the sides weren't parallel.
I scribed an outline on the girdle and trimmed the slab on my 8" trim saw (took about 20 minutes of trimming) until both sides were closer to being parallel.
Next I scribed a center line on the preform and two lines on either side to use as guidelines for grinding the domes on each side.
These next two photos show the (almost) completed cab. Unfortunately there was a small fracture in the clear opening of the pattern on the bottom that propagated to about 1" long as I was working the cab.
I subjected the fracture to an Opticon treatment and it significantly sealed it.
The completed cab. It is 4-1/2" across and destined for my display case.
Here is a photo of the side showing the double dome of the cab.
Bob
