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Using Designer Stone Cabochons In Jewelry

Using Designer Stone Cabochons In Jewelry

Posted by Barlows Gems on 18th Apr 2023

Are you ready to start working with Unique and High Quality stone cabochons?

Today the mainstream jewelry world has come a long way. No more plain old gold and diamonds or fake plastic stones. Today many unique and rare gemstones are being cut into designer cabochons. A cabochon use to be described as a domed stone (usually an oval shape) cut for jewelry with a flat back. Now we have many other shapes including freeforms and fancy cuts, and even natural crystal tops! Gemstones that were once only bought by collectors are finding their way into amazing one-of-a-kind jewelry pieces!

There is a plethora of cheap stone cabochons out there. Some can be very pretty and they are certainly cheap enough. But if you truly want your jewelry to be a work of art, if you want to build your reputation as a true jewelry artist, then it is important to invest in quality designer cabochons.

There are several factors you should consider when learning how to set, store and wear your designer stone cabochons.

HARDNESS OF STONE CABOCHONS

Gemstones come in many different hardnesses. But for purposes of determining how to set or care for your stones, it is important to know the hardness. In the rocks and gemstones world we use the Mohs scale.

The Mohs scale of mineral hardness (pronounced as it looks- mohz) is a number scale, from 1 to 10, 1 being the softest to 10 being the hardest. This scale is based on the scratch resistance of minerals through the ability of harder materials to scratch the softer materials.

The Mohls scale was introduced in 1812 by the German geologist and mineralogist Friedrich Mohs. However, the method of comparing hardness by observing which minerals can scratch others has been around much longer, having been mentioned by Theophrastus in his treatise On Stones, c.  300 BC, followed by Pliny the Elder in his Naturalis Historia, c.  AD 77.

The Mohs scale is as follows:

  • 1   Talc (easily scratched by a fingernail which has a hardness of about 2.5)
  • 2   Gypsum
  • 3   Calcite (Copper has a hardness of about 3)
  • 4   Fluorite
  • 5   Apatite (Glass has a hardness of about 5)
  • 6   Feldspar (Steel is about 6.5)
  • 7   Quartz
  • 8   Topaz
  • 9   Corundum (Ruby)
  • 10   Diamond (cannot be scratched by any other natural substance)

Many minerals fall in between the levels (steel is 6.5) or can actually vary a little in their hardness (pearl is 2.5 to 3.5). And unfortunately many semiprecious gemstones are made up of different minerals with different hardnesses present in one stone cabochon. One strong example is Chrysocolla. Chrysocolla can run from 2 to a 4, but if silica is present it can actually be a 7. Often Chrysocolla is found with another mineral, such as Malachite, which is a 4-so if the Chrysocolla is a 2 the stone will have 2 different hardnesses. This can lead to undercutting when cabbing a Chrysocolla-Malachite stone!

In general agates and jaspers are in the quartz family (along with tiger-eye, flint, fire agate and petrified woods), meaning they are a hardness of 7 and work really well in all types of jewelry. However, remember that some stones named "jasper" are not true jaspers and may be softer.

TOUGHNESS OF STONE CABOCHONS

The Mohs scale is useful for identification of minerals in the field, but is not as accurate a predictor of how well materials endure in an industrial setting as toughness. Remember, hardness identifies if the stone can be scratched, but toughness or brittleness determines how easily the stone can break. Toughness is usually related to cleavage. In mineral terms, cleavage describes how a crystal breaks when subject to stress on a particular plane. If part of a crystal breaks due to stress and the broken piece retains a smooth plane or crystal shape, the mineral has cleavage. A mineral that never produces any crystallized fragments when broken off has no cleavage. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the microscope and to the naked eye.

Diamond, the hardest material, is in fact quite brittle. Fluorite is known for having perfect cleavage in all four directions. Jade is actually the toughest stone.

Another important thing to know about stones is their stability. How does the stone react to chemicals, heat, humidity, and light.

Sudden and extreme changes in temperature can create fractures and cleavages or cause existing ones to spread in many stones. One should always try to avoid exposing your stones to sudden changes from very hot to very cold temperatures. This sudden temperature change will damage gems such as apatite, iolite, kunzite, opal, and tanzanite.

Opals should not be stored in extremely low humidity. In addition, long exposure to water can damage some gems, such amber, azurite and malachite.

Citrine, amethyst, kunzite, and topaz can fade or change color from prolonged exposure to light. Also long-term exposure to heat and light can damage most organic gems such as amber, pearls, jet, coral and ivory.

Chlorine, and even perfume and some makeup can damage or discolor delicate and porous gemstones like pearls. Chlorine can also damage white gold mountings. Ammonia will damage the polish on many softer gems such as malachite, turquoise and coral.

Finally, be aware of stabilized or treated stones when cleaning. These treatments can be damaged by ultrasonic cleaning or exposure to alcohol or other organic solvents. Turquoise can easily absorb different liquids, including oils or even perspiration, which may discolor it.

Now that I have scared you-let me assure you that for centuries people have made, worn and enjoyed jewelry with unusual and beautiful stone cabochons that with proper care and common sense can last indefinitely!

Though there are many stone materials that people will tell you are unsuitable for jewelry use, I believe that most gemstones can be used for jewelry! Don’t be afraid of stabilized stones. Sometimes this is the best way to protect your stone. Stabilization or treating is usually done by impregnating a porous stone with a resin or plastic substance. Think Turquoise, most turquoise on the market is stabilized. Generally, this type of stabilizing or treating a stone just makes it more durable, it does not change the stone or devalue it.

Stones that have cleavage or are brittle should be set in with special techniques or in secure bezels to protect them. A bezel is a band of metal that actually surrounds the stone. Bezels are great for all types of stones, can be easier to use to set stones, and are not as likely to snag or get pulled like prongs do and have the stone fall out. Wire wrapping can also protect and secure the stone well.

I do say that some stones are better set in pendants rather than rings. Rings with more fragile stones should be worn only for special occasions and especially not doing heavy work with your hands, such as gardening, rock collecting, or when immersing your hands in liquids or oils. Pedants should be on shorter chains on stones that break easy, so there is less swinging and banging.

CLEANING YOUR CABOCHON STONE JEWELRY

Usually, cabochons should just need to be wiped with a soft lint free cloth. You can use a rouge cloth on metallic stones that have native copper or silver (such as Mohawkite) in them, as they do oxidize.

When you are ready to set your stone cabochon in a jewelry piece, it is always best to make sure the metal is completely polished before mounting. If you have to touch the metal up after mounting, make sure you don’t hit the stone. I only recommend touching up the stone with polish if you have some lapidary knowledge of what buffs and polishes to use on what materials.

Once set the best and safest way to clean your stone cabochon jewelry is with water, a liquid soap such as Palmolive, and a soft bristle toothbrush. Gemstones (like diamonds and most faceted stones) that are not damaged by ammonia might clean better with it, and ultrasonics are great for gold, diamonds and harder faceted precious gemstones, but I don’t recommend using an ultrasonic or harsh chemicals on semiprecious stone cabochons. Sometimes you may need to use a toothpick or a pressurized water spray (think Waterpik) to dislodge excess polish. 

Gold and silver can be cleaned or shined up with a rouge cloth, but don't use it on the stone cabochon unless it is a metallic stone. Wipe or dry with a soft lint-free cloth.

STORING YOUR CABOCHONS OR YOUR STONE CABOCHON JEWELRY

Cabochons of the same material can be stored together in one tray or if not being move too much, in a bag together if they are at least a 4 or higher. But cabochons of different materials should never be left to rub against each other. Softer stones should never be stored in a bag even if they are all the same. I have had bad experiences with Coquina Jasper and Angelite! Stone cabochons are best protected in trays with individual compartments, in individual plastic bags, or some people use double sided sticky tape to tape them to cardboard strips.

Your stone cabochon jewelry should never be just thrown together in a box or drawer. Even gold and silver can scratch that way! All jewelry should be separated. If you want to use a box, put each piece in its own cloth bag or even plastic bag. I like to use the plastic so I can easily see what piece I am looking for. There are lots of companies that sell jewelry display and supplies.  Trays are available where each piece has its own compartment, there are ring inserts with slots that are great for storing or displaying rings for sale. Jewelry rolls are nice for traveling or taking inventory to trade shows.

Another great idea for both cabochons and stone cabochon jewelry to store and travel with is one of the craft clear plastic boxes with separate small compartments.  Then necklaces can be put on display "necks", and rings on ring holders.  Earrings are usually stored and displayed on cardboard squares with the post or clips secured through holes. Stone cabochon sets with earrings and a necklace with a pendant can be pinned to velvet boards as shown in the picture.  

Thanks for reading!