GEMS

Calling this page "gems" at this point in my career is a bit pretentious but everything has to start somewhere.

My most recent obsession has been learning how to cut gems. Somehow I had this image of little people in Amsterdam chipping away at diamonds with tiny rock hammers.

I finally got motivated to learn more about it and here I am.

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HALF BRILLIANT

My first attempt was to do what is called a "Brilliant Cut" on a marble that my wife donated. By the time I finished the 33 facets on the crown, it was obvious that this was not going to be very brilliant so I just finished the pavilion or bottom with 8 simple facets and moved on, learning from my mistakes.

Simple Jack

My second attempt is a "much easier" cut known as Simple Jack, also on a glass marble. This has fewer facets than the brilliant but even at that, I managed to misinterpret the protractor and got all the angles wrong but it was another great learning experience.

Among other things I learned is how beautiful the lowly marble becomes when cut as a gem.

Phase Two

This grouping represents several steps up in my cutting evolution. The top stone is what is known as an "emerald cut: on a piece of amethyst that my wife had in her rock collection. It is a beautiful stone but some problems with the faceting machine left me with something less than a perfect rectangle.

The two on the bottom are nearly perfect cuts made after some serious changes were made to the machine. They are both cut from marbles.

Pendant

One of the problems with this craft is how to turn these "gems" into gifts. They need to be mounted in something so they can be worn rather than tossed into a junk box. Buying or making rings is a bit of a leap just to give away a gemstone so I came up with this pendant design that can be worn on a chain using a nearly free finding. After unscrewing a barrel clasp, the stone was epoxied into the threaded end and the other half thrown away.

This pendant was made from a 1" marble and easily scales down to a small marble for earrings.

I think it's safe to say that I have come a long way since the first marble.

From left to right we have:

1. Emerald cut green marble, white topaz, synthetic ruby, amethyst

2. Bracelet: Cabachon cut green stone found in garden, brilliant cut Cubic Zirconia , Cabachonecut synthetic Ruby, CZ, Cabachon cut synthetic Saphire

3. Pendant cut from marble, round brilliant cut from smoky quartz, round brilliant cut from garnet colored CZ, Pendant cut from Sunstone.

This is the one I wanted for my wife when we got engarged but had to settle for something a little smaller.

This is an 11.5 carat Cubic Zirconia that is about as wide as her finger.

I always wanted a jewel studded wine glass so I bought this silver one on Ebay and spent a great deal of time making 8 cabachon rubies out of synthetic corundum.

The upper ones are 12 x 14 mm ovals and the bottom are 10 mm rounds. They are set in Easyset findings purchased from Tripps and soft soldered to the cup.

This piece represents several new technologies I have been getting into.

The cup again from Ebay, is a very large brandy snifter.

I sand cast the 2" Maltese Cross in fine silver and spent hours, filing, sanding and fitting it to the curve of the cup. The central stone is a brilliant cut, saphire colored CZ set in a cone shaped hole and held in place with four prongs hard soldered to the cross.

The prongs were made by drilling holes and inserting silver wires which after soldering, were trimmed, notched and bent over the stone.

The four cabs are set in bezels made from purchased flat bezel material, soft soldered to the cross, and burnished over the stones.

The green cabs are Amazonite found in the garden this Spring while tilling and the other two are as yet unidentified stones also found in the garden. They are are pearly white with red streaking and look exactly like blodshot eyes.

The cross with settings was tumbled to a beautiful luster and after setting the stones, the entire piece was gold plated for contrast with the silver cup.

This piece is a variation on the above theme. The cross is a bit larger and the cab vs faceted stone positions have been reversed. We have a ruby cabachon surrounded by 4 faceted CZ's.

The cross was cast in fine silver and all the stones are bezel set and the entire piece was 24 K gold plated.

The new technology here is really in the Etruscan chain.

The .050" wire for the chain was rolled from fine silver using a home made rolling mill that occupied me for a few weeks. The wire was formed into .5" rings and solder joined. These were then flattened into loops and linked into the chain. Marilyn and I did this over a two week period and called it my knitting.

This picture is a collection of some of the rings I have made using stones that I cut. I started using commercial rings and then got into casting and forging my own rings.

The list below identifies them, left to right, top to bottom. Commercial setting unless indicated otherwise.

1. Star Ruby, cabachon cut
2. Red marble, 8 sided brilliant cut
3. Synthetic Ruby, cab cut
4. Synthedit Ruby, 8 sided brilliant

5. Amazon Stone, cab cut in hand forged ring.
6. Green Marble, Standard Round Brilliant (SRB)
7. YAG saffire simulant, SRB
8. YAG emerald simulant, emerald cut, hand forged ring

9. CZ emerald simulant, SRB, hand forged
10. Amythist, cab, hand forged
11. Synthetic saphire, 8 brilliant

12. CZ, SRB, hand forged
13. CZ SRB
14. Strontium titanate (Fabulite) , SRB (see below)

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FABULITE

Fabulite is the Madison Ave name for a most amazing man made gem material with the unappealing name of strontium titanate.

It has a color dispersion value about 10 times as high as diamond and produces fire that looks like a Christmas tree by comparison.

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Tiny Rock Hammer?

Not surprisingly, cutting gems has nothing to do with rock hammers. It is done on a faceting machine and the word cutting is pretty much of a mis-nomer. Each facet is ground to the proper angle and then unground and polished.

These machines cost from one to many thousands of dollars. As one who enjoys making things as much as using them, I built this one pretty much from stuff around the shop.

The machine and the whole process, for that matter, has a lot in common with my previous experience with lens and mirror making. The stone is ground and polished against the appropriate rotating lap. The stone is glued to the dop which is held in a the movable platform that has adjustments for angle, rotation around the axis of the stone and vertical height.

For more info.....EasyGem

Each facet must be ground to the correct angle, size and location and then the lap is changed at least 3 more times to bring it to a polish. The basic lap is just a copper plate that is charged by rolling diamond paste into the soft copper.

This is all simple enough but the devil is in the details. The brightness and fire of a gem is a function of maximizing the amount of light that comes back out of it and the amount of dispersion to provide rainbow sparkle. The angles are calculated as a function of the refractive index of the gem material and the faceter does his best to get them exactly right for maximum brilliance.

The other detail is that all the facets must meet evenly and exactly at the proper places. Any deviation from perfect meeting is a defect and reduces the value of the gem. Click here for an example of the type of detail involved in the Simple Jack .

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