My expertise comes from 17 years of laboring many hours over various lapidary machines. I had to learn how to use these machines in order to finish 1000's of designer cabochons. My training started at the Mineral and Gem Society of Santa Rosa where I learned the basics on how to create a cabochon. My main goal was to create something that would be enjoyed by collectors and jewelry designers. Starting out was the toughest part, taking criticism was part of the learning, not everything I created was topnotch, a lot of people had good suggestions which I appreciated and only made me better at this art.
The type of rough material you buy for designer cabochons really depends on the type of machines you have access to. Diamond lapidary saws, grinding, polishing, tumblers and buffers are the major machines needed to start and finish most lapidary jobs. My suggestion is to join a local Gem and Mineral Club that has a work shop containing all the machines and the expert help you will need to finish your first designer cabochon. The knowledge you gain as a member will be extremely valuable especially if you want to move your work base to your own shop. Many persons starting out at their local Gem club not only find the help they need but also new friends that can relate to your new interests..
Selecting material to work on
I like to keep my eye out for what's new (recent finds) and scarce and rare material that's generally sold at estate sales and sometimes at the Gem shows. Of course when I started out I picked out a lot of different type of material. To me, everything had the potential of turning out to be an outstanding Designer Cabochon. I now have a yard full of wonderful looking rock. And some of it is just that, just rock and not really good for cabbing or jewelry.
One thing I did learn from all this buying is when you buy a slab (a piece already sawed from the base rock), "Don't buy it until you dry it off". Most dealers will sell their slabs in water because the water brings out the colors, just as if it was polished. This water will hide cracks and pits. You will find this tip really important. When you look at a slab you will want to vision the cabochon coming from an area that doesn't contain a crack or pit so the slab has to be dry. If it's your intention to make wire wrapped jewelry, fine handmade jewelry or sell to designers, cabochons do not look their best with unsightly cracks across the face of the cab.
Another tip to selecting your slabs or rough is to know the hardness of the stone or better yet ask to see a sample polished cab if available. Soft stones on the hardness scale will not normally produce a mirror polish. Even so, I've had a lot of soft material that does produce a mirror polish will a little extra work. Most times it produces a bright luster. One way to determine if it's hard or soft is, if the water runs off the slab it is hard (dense). If the water is absorbed into the slab it is most likely soft and the polish won't be mirror like.
One tip on selecting a rough rock, make sure it will fit into the diamond saw you will be using. All saws have a limit to the maximum thickness of the rough. My yard also has a supply of large rocks that won't fit into my saws. Selecting a rough rock is not the same as selecting a slab. In a slab you can definitely seen what you are buying so you're not taking a chance not getting something you can't use. Sometimes the dealer will also have slabs available, ask to see them. If you're at a Gem show there may be someone there that could cut a large rock if you really had to have it.
Fun places for slabs and rough
Rock and Gem magazine is a good source for listings
Local Gem and Mineral club sales - annual shows in all U.S. states
Quartzsite, Arizona Jan and Feb annual flea market and gem shows
Tucson, Arizona, Jan and Feb annually - by far the biggest show everywhere in town
Denver, Colorado twice yearly spring and fall - many shows across town
Good Luck on your new interest, you're going to experience a lot satisfaction.
Bruce W. Frymire author and creator of this guideline on selecting material for Designer Cabochons. On my website, https://designsbyshirl.com, I have many pictures of cabochons I have finished. This is a good resource to help you identify the material you may want to use for your projects. If your path will be to create handmade jewelry then my designer cabochons may be what you need. If you need a quick jewelry gift, check out Shirl's wire wrapped jewelry using my designer cabochons or my ancient coin jewelry that uses Greek and Roman coins to create pendants for both men and woman.