Cabochon Stone Buying Tips

A few of the many different types
and sizes of cabochons that are available for inlay.

Overview

Few aspects of the woodturning arts have been as interesting to me as inlaying. Through the years, I've inlaid many different types of materials into my woodturnings including various metals, wood, stone, composites, bone, shell, antler and glass to name a few. One of my favorite materials to work with is polished stone cabochons.

These are typically inlaid into bottle stoppers, boxes, pen caps, letter openers, platter rims and many other types of projects. My explorations into inlaying have produced some of my most favorite pieces and it's been a tremendous asset for me in my continued growth as an artist. I currently inlay over one hundred different types of polished stones and agates, in various sizes ranging from 1.5mm to 38mm in size.

Knob Thorn with 25mm Fancy Jasper inlay.

Most woodturning suppliers carry a limited selection of cabochons, so if you really want to explore inlaying, you need to look for other sources like jewelry, or lapidary suppliers. There are two basic types of lapidary suppliers, resellers of cut stones and manufacturers that custom cut stones to your order.

In your quest to find a larger variety of stones in the round, you will find that the selection is quite limited with most suppliers. Oval and freeform cabochons are much more popular in the jewelry trade than round stones it seems, but you can still find a good selection of rounds at most suppliers.

Here are a few buying tips that will help insure you receive good quality, correctly calibrated stones for your inlay work. These tips were developed from my personal experiences (both good and bad) of buying large amounts of polished stones and agates over the last twelve years from U.S and international suppliers.


Woodturners vs. Jewelers

Woodturners and jewelers have very different needs when it comes to the types of polished stone cabochons we can effectively use. If you're making jewelry, you can usually adapt the project (ring, bracelet, necklace etc.) to fit many different shapes and sizes of cabochons. Unusual shapes like ovals, teardrops, crystal cuts and others can be easily inlaid into most jewelry settings.

However, when you want to inlay a cabochon into a woodturning (a bottle stopper for example), your design choices are limited. Since we are typically inlaying our cabochons into round recesses, we need round stones with flat bottoms, but not just any round stone will do…


Cabochon Stone Buying Recommendations

  • Look for stones that feature uniformly domed tops with rounded edges, or flat tops with rounded edges at the bottom of the stone. Do not accept stones ground to a knife-edge at the bottom!
  • Lots of cabochons are ground to a knife-edge where the domed top meets the flat bottom. This knife-edge is not a problem for jewelers, but it creates significant challenges when inlaying the stone into wood. The knife-edge is very fragile and prone to breakage during shipping and installation.

Nigerian Ebony with 25mm Turquoise and 3mm Turquoise around band.

  • Note: Successfully inlaying a knife-edge cabochon into a woodturning can be done, but the recess is more complex and requires turning the recess as two separate parts, which are subsequently joined after the stone has been inlaid. These two part inlays are called binding ring inlays, because the supporting ring acts as a retainer, or binding ring for the cabochon.
  • Look for stones that are highly polished, with a uniform luster across the face of the stone. Since some stones are manually polished, the quality of the polished surface can vary. Do not accept stones with dull areas, or flat spots on an otherwise domed surface. These are signs of poor grinding and polishing during the manufacturing process.

Cocobolo bottle stopper inlaid with Crazy Lace Agate and 2.5mm Signity presets around the band.

  • Stones should be free from obvious defects like pits, or cracks in the visible surface.
  • Some stones are "enhanced" by one or more processes to change the color, or look of the stone. If the stone is entirely natural, it should indicate this clearly. Most suppliers will tell you if a stone has been enhanced, or altered in some way. However, if this is a concern to you, be sure to ask before your order.
  • Rare stones can be very expensive. For example genuine (naturally occurring) Malachite and Azurite mixed in the same stone. If you see a rare stone listed that seems inexpensive, you can bet it's probably a man-made, or an imitation stone. This should be noted in the description, but always ask if you're unsure. The price difference between a man-made stone and a genuine natural stone can be significant.
  • You're probably thinking this is not that much to ask for right? Well, yes and no. If you choose your suppliers carefully, you'll probably be ok. However, even with the best suppliers, you have to check every order for stones that do not meet your specific quality requirements.

Woodturning Supplier - Buying Tips

Most of the well-known woodturning suppliers offer polished cabochons for decorative inlay in the popular 25mm round domed size, as well as a few other sizes. For the most part, these stones are well calibrated and uniformly polished with nice round edges. Although the overall selection is limited, you can usually get very good quality stones that will be easy to inlay.

Nigerian Ebony with 25mm Rhodochrosite inlay and 2.5mm white cubic Zirconia inlays set in 14K yellow gold.

However, you still need to check each and every order, as I've gotten some stones that were poorly polished, or incorrectly finished with knife-edges on occasion from some woodturning suppliers. Ask about the return policy before buying, just in case you have to send an order back because it does not meet your quality requirements.


Jewelry Supply Company - Buying Tips

If you're looking for a bigger selection than what the woodturning suppliers offer, check out jewelry supply companies. Most jewelry suppliers require a minimum order, but carry a nice variety of polished round cabochons in various colors and sizes. If you're into small-scale turnings, jewelry suppliers are the best place to look for stones 10mm or less in diameter.

Selling prices can and do fluctuate! I've had stones more than double in price from the time they were ordered. Depending on the supplier, you may be responsible for any price increase that occurs before the order was shipped. Most of the better companies will let you know about price increases and give you the opportunity to cancel the order. To protect yourself, ask before you order what the policies are regarding price increases.

There are lots of imitation, or man-made stones available. Some of the man-made stones are difficult to tell from the real ones. Therefore, try to limit your suppliers to places you can visit firsthand, or places you have dealt with in the past and trust. If you're unsure, ask if the stone is natural, or man-made before you order.


Direct Importers and Foreign Lapidary Supplier – Buying Tips




Various bottle stoppers inlaid with polished round cabochons.

If you're looking for an even larger selection of stones, there are numerous direct importers and foreign lapidary supply companies that offer polished stone cabochons. Most foreign supply companies are good folks to do business with however, some can be very difficult. They may require large minimum orders and they usually will not deal with hobbyists. Most will require that you have a business and/or pay for the entire order up front. Something always seems to get lost in the translation and the quality can vary from excellent to poor. Due to market fluctuations, the prices may change and you may end up paying more than you expected for your order when it arrives. Shipping varies as well, from fast and efficient to slow and slower.

Many foreign suppliers will custom cut your order from the rough stone and therefore, it is non-refundable once your order is processed. If you choose to go this route, ask lots of questions before your order and make sure you understand the ordering and shipping process. It's also a good idea to submit a small test order, to see the quality of the stones you'll receive and how fast they arrive.


Recommended Sources To Get You Started

  1. Craft Supplies U.S.A., Provo, Utah. 1-800-551-8876 They carry a small, but nice selection of stones in the round.
  2. Fire Mountain Gems, Cave Junction, Oregon. 1-800-423-2319 This is a jewelry supplier that carries a larger selection than Craft Supplies in the round, but many stones are only available in 10mm, or smaller sizes.
  3. Rio Grande, New Mexico.1-800-545-6566. This is another jewelry supplier that has a large selection of round stones that are well calibrated and polished. They carry some of the harder to find stones and agates.
  4. Hong Kong Lapidary, Coral Springs, Florida. (954) 755-8777 This is a lapidary supplier that carries a good selection of round cabochons in various sizes. They carry some of the more unusual stones and rare agates.

Additional Sources

Many of the stones I use for inlay are obtained at various rock shops and lapidary suppliers in New Mexico. On my annual trip to the BYU woodturning symposium in Provo Utah, I will usually stop off and check out the inventory at several rock shops. Most major cities have lapidary suppliers that can be found in the Yellow Pages. These local companies offer the distinct advantage of allowing you to see and judge the quality of the cabochons firsthand.

If you still need more suppliers, a quick Internet search (use the keywords "lapidary supplies" and "jewelry supplies") will list thousands of jewelry and lapidary supply companies. If possible, try and visit a new supplier before ordering so there are no surprises when your order arrives.

If that's impractical (out of town, or out of the country supplier), use small test orders to judge the quality and promptness of delivery before making a large order. This has worked well for me in the past with U.S. and international suppliers. Once you feel confident in the quality of the stones, you can order larger quantities.


Final Thoughts

I hope these tips will help you to choose the best quality stones to purchase for your woodturning inlay work. More information about my protocol for inlaying polished stone cabochons into bottle stoppers is available here.


Safety Note: Always follow all manufacturers safety instructions before working with your lathe, or any of the tools or products you may use. If you are unsure about any operation, obtain competent professional instruction before proceeding. Use and wear all necessary safety devices during turning and observe safe woodturning practices to prevent accident or injury.


Steven D. Russell is a professional studio woodturner, teacher and writer. He has written numerous articles for international woodturning magazines, which have been published in more than 78 countries around the world. Steve has demonstrated in numerous cities across the United States. His studio, Eurowood Werks, specializes in bowls, platters and hollow forms with unique visual and tactile treatments.

Steve is also the current and founding President of the Lone Star Woodturners Association, Inc., an AAW member chapter. The LSWA is a 501(c)3 non-profit educational organization dedicated to teaching and demonstrating the art and craft of woodturning.

Steve is also a featured writer for the Guild of Master Craftsman's "Woodturning" magazine, published in London England. Woodturning magazine is the world's leading magazine for woodturners. Look for his articles covering technical topics, or project based articles in an upcoming issue.