Cabs and Stones: Like Candy for Jewelers

13 Aug 2010

Helen Driggs
is the Managing Editor
for Lapidary Journal

Jewelry Artist
What's Your Favorite Color?
This Royal Sahara Jasper brooch was an interesting design challenge. I didn't want to obscure the raw edge on the lower right of the cab, so the tube set sapphires served as a security "prong" to support and protect that region of the stone.

I love stones. Faceted, cabbed, rough, smooth, raw, finished, matte, or polished, any color any size. Stones are like candy for jewelers. Whether you cut them yourself or buy them, most of us can admit the reason we fell in love with jewelry making was because of the allure of some fantastic stone we saw in the distant or not so distant past.

There are things to consider when using cabs and stones in your work. Here are tips for choosing stones to make your time at the bench easier, rather than harder. And the same tips apply no matter which side of the grinding machine you are on--even lapidary artists should keep the final use of the cab they are cutting in mind as they grind!

Shapes and Colors
Funky shapes are cool and interesting, but sharp direction changes or very pointed corners are a fabrication challenge and will often dictate how you must set the stone in a piece. A bezel may not always work, so if you don't want to make prongs or something more challenging, watch those corners.

And, sure, that blazing, electric blue drusy is just fantastic, but will your customers think so, too? Just because you like certain colors doesn't mean everybody does; so if you plan to sell what you make, try to purchase stones in many colors and shapes to offer choices to your customers.

Odd or raw surfaced stones require a different setting strategy than the typical calibrated oval. Plan the piece carefully if you are using materials like this geode from Mexico or schist with a raw garnet in it.
Is the back of your cab flat? If it isn't, you'll have to adjust your design to support the irregularities on the back of the stone. That will add to your fabrication timeline and the cost of more metal. And, if you are cutting your own, make your life easy--get thee to the flat lap!

Raw Material
Is the material you want to use brittle or delicate? Trust me--buy an extra one or enough rough to cut a replacement stone. You really never want to break a stone, but it happens at the grinding wheel and the bench--and always at the endgame. And does the cost of the stone fit your budget? Will it fit your customers' budgets when you're done making a piece with it?

Make Room for Friends

If you cut your own stone and you fabricate jewelry as well, you really have the best of all worlds when it comes to acquiring material. Here is some sweet ruby in zoisite rough--fantastic green and purple all stacked up and waiting to be slabbed. Juicy!

Don't forget to buy smaller accent stones. I know it might seem boring to get a bunch of plain round, 10- or 12mm stones, but at 3 a.m. when you decide you need an accent stone to finish a pendant, you'll be glad you have them on hand. It often pays to purchase stones in quantity. If it's a cut or material you love and your customers love, buy enough to get a price break. Ask the cutter how much that is and go for it.

Do you have enough experience to set the stone confidently? By all means, buy it if it's a good price, but realize practice makes perfect, and you might hold a cut stone for a while before you use it. You'll know when you're ready.

Size Matters
Big, giant, gorgeous stones are beautiful. But that means weight. You'll need a lot of metal around a big stone to support it. Thick or deep stones equal deep bezels, so you'll end up fabricating those from sheet instead of ready-made strip.

No Regrets, No Prisoners
If you see something so fantastic you have to have it, you can afford it, and you will make a piece from it, buy it. The funny thing about gem material is that it is a limited commodity. You may never, ever see that kind of stone again, and regret really is a terrible thing. If you think you'll be "haunted" by a cab you love, buy it, and make a present for yourself.

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JanineB@7 wrote
on 13 Aug 2010 3:24 PM

Helen great article and how true everything you have touched upon. I am a rock nut and somewhat of a hoarder when it concerns my stones. The very first piece that I bezeled was a moonstone and I chose it to go with a necklace that I had mad that had the same color in it. Well,,,,,,the stone was not flat on the bottom and I had a heck of a time setting it. What I had to do was insert a piece of sterling wire around the stone on the inside of the bezel. That was not the big problem..Next I had to work the bezel around the stone to set it. The stone kept trying to pop up and out making a fairly simple set take an awful long time to accomplish. Hense...flat is good !!!

I have an end slice of a wonderful Watermelon Tourmaline that is not faceted and it has such great color and reminds me of a mini mountain terrain. The octagon being the end or the beginning of the 1 1/16" wide crystal has been cut on an angle. Being determined, by nature, I built up the irregular slice with  silicone and now have a perfectly uniform stone to work with. My delema is...will the stone break when I try to set it??????I have cut my bezel out of fine silver and the base has been cut out of Sterling Silver sheet. I so do not want to break this stone and I have been putting off setting it...I am so scared I will ruin the rock. I look at it once a week and after a year and a half later I have yet to complete it. This will not be for sale once I have completed it...I almost feel like Gollum and this is my precious and nobody else will lay claim to it.

Just had to share and I really like the article that you have written. I know I will refer back to it often and it has given me inspiration to try to move forward with my favorite rock.



LennieP wrote
on 18 Sep 2010 7:16 AM

Hi Helen, I enjoy your blog.  I live in Wyoming and haven't made it to any of the big shows.  Where can one get good quality cabs in a variety of cool and colorful materials by internet or mail?  Also, I would love it if the photos in the blog could be resized so we could look at the work, for example the Sahara Jasper piece in this is sooo small and I would love to see it more closely.  Thanks, Lennie