Gemstone Treatments

Though not commonly known to the public, many gemstones are treated in some way to enhance their color and clarity.  These treatments are common and widely accepted in the industry, and normally do not de-value the stone.

Most retail jewelers do not divulge this information to their buying public and sometimes they themselves are not aware of it.  If they are a reputable and ethical establishment, they will be honest if queried on the subject.  Don't expect this information to be offered without inquiring first.

The most common treatments used on natural stones that I have come across are listed and explained here.

Heat treatment is the exposure of a gem to high temperatures to alter its color and/or clarity.  This is the most common method used to color enhance gems.  The most common gems that use heat treatment are:  amber, aquamarine, amethyst, citrine, ruby, sapphire, tanzanite, topaz, tourmaline and zircon.  Heat treatment is considered durable and permanent under normal handling conditions.   The heat may render the gems slightly more brittle than usual, so care must be taken not to damage pointed faceted corners and edges.

Dyeing introduces colored dyes into porous or fractured gems to change their color. Such fractures are sometimes purposely induced by heating the gem so that an otherwise non-porous material can more readily accept the dye.  The most common gems that are dyed are:  pearls, coral, turquoise, lapis, howlite, nephrite jade, chalcedony, quartz, emerald, and ruby.  Dyed gems can be quite durable, but is ultimately dependent on the stability of the dye itself.  Many dyes can be removed if the gem comes into contact with a solvent such as alcohol or acetone.  Some dyes are unstable with exposure to the ultraviolet in sunlight and can fade over time.  The best treatment for dyed gems - care must be taken to not bring them in contact with chemicals such as acetone or alcohol, which could dissolve the dyes, or have them exposed to prolonged periods of sunlight (such as leaving it on a sunny window ledge) which could cause the dyed colors to fade.

Surface Coating alters a gem’s appearance by applying a coloring agent like paint to the back surfaces of gems (a treatment known as “backing”), or coating the  gems surface with such enhancements as lacquering, enameling, inking, foiling or sputtering of films to improve appearance, provide color or add other special effects.  The most common gems that use this treatment are:  diamonds, tanzanite, topaz, coral, pearls, and quartz.  Coated gems tend to have a softer surface and/or the coating may not adhere well to the underlying gem.  These thin-film surface coatings are susceptible to scratching, particularly along facet edges and junctions.  Do not allow any hard or abrasive objects to come in contact with coated gems.


Impregnation stabilizes porous gemstones using a colorless bonding agent, such as polymer, wax or plastic, to add durability and improve appearance.  The most common of these gemstones include:  turquoise, lapis lazuli, jadeite, nephrite, amazonite, rhodochrosite and serpentine.  Many impregnations are often “skin deep” and due to the melting point of plastic and wax, can be susceptible to heat damage. Plastic impregnations are considered durable in gem materials such as turquoise as long as they are not subjected to heat or chemicals.  Care must be taken not to subject gemstones with wax or plastic impregnations to heat, such as that encountered by a jeweler’s torch, since these will likely melt the material.

Irridation uses neutrons, gamma rays, beta particles or high energy elections to alter the color of gemstones.  This is sometimes followed by a heat treatment to further modify the color.  This second step also known as a “combination treatment.  The most common gems that use this treatment are:  diamonds, corundum, topaz, pearl, quartz, some varieties of beryl and spodumene.  Some irradiated gems’ color fades upon exposure to strong light.  Blue topaz, diamond and quartz tend to have very stable colors as long as they are not exposed to high temperatures.  Irradiated colored diamonds' colors may be damaged if the diamond is exposed to the heat of a jeweler’s torch.  In the beryl and spodumene gemstones, the irradiated color tends to be short lived and fades upon exposure to bright light.

Fracture or Cavity Filling is filling surface-reaching fractures or cavities with a glass, resin, wax or oil to conceal their visibility and to improve the apparent clarity of gem materials, appearance, stability, or in extreme cases—to add to a slight amount of weight to a gem. The filling materials vary from being solids (a glass) to liquids (oils), and in most cases, they are colorless (colored filler materials could be classified as dyes).  The most common gems that use this treatment are:  diamond, ruby, emeralds, quartz, aquamarine, topaz, tourmaline and other transparent gems.  Durability?  Much depends on the filler. Glasses tend to be harder and therefore more durable than resins, oils or waxes. Changes in air pressure, proximity to heat, or by exposure to chemicals can all affect the appearance of filled gems by potentially altering or removing the filler substance.

Diffusion uses chemicals in conjunction with high temperatures to produce color and/or asterism, or star like, producing inclusions as in the star sapphire.

Bleaching is using a chemical to alter or rid a porous gem of all of it's color.  Some gemstones are bleached and then dyed, a form of “combination treatment.”  Jadeite jade, pearls, coral, chalcedony and tiger’s eye quartz may be bleached to lighten their color.

Oiling and/or Resin Infusion is filling the surface of breaking fissures in gems with colorless oil, wax, resin or other colorless substances, except glass or plastic to improve the gemstone's appearance.

Waxing is the impregnation of colorless wax, paraffin and oil in porous, opaque or translucent gemstones to improve appearance.

There may be more ways in which gemstones are treated to enhance their color and durability.  These are the more common ones I have come upon as a gemstone buyer.  If possible, try to purchase untreated gemstones.  Know that because they are more rare, they will also be a higher price than treated gemstones.

(Information for this article has come from 2 sources: from the blog Unicorn's Garden and the GIA website)

Cleaning Silver Plated Jewelry

When you look at Maria Bella Jewelry, you will notice some of my pieces are made with sterling silver components and some with silver plated components. Silver is usually plated over brass in jewelry and is less expensive. The cost benefit is the reason that I use plated silver. Plated silver jewelry is less expensive to make and easier to afford for many customers. The plated chain and other components I have found look just as nice as the sterling silver jewelry parts that I have. The plated pieces will probably not last as long as the full silver ones.

Silver plated jewelry, like sterling silver jewelry, will tarnish over time. But there are care techniques you can use to extend the life of your jewelry piece. I found this care information written on the web by Nancy Janeliunas of Janeluinas Jewelry. It sounds like good solid advice to me.

"To remove tarnish from silver plate, use the same techniques or solutions that you would with solid sterling silver items. However use the least amount of polishing (or shortest exposure time needed to liquid dips) as necessary because any process that removes tarnish also removes minute amounts of silver on the surface. Over time the plate will eventually wear, some plates are thicker than others so a heavy plate will most likely last a lifetime with proper care.

To advise which is better using a chemical dip tarnish remover or a polishing cloth. I would first say that depends on the item. If there is porous stones (Turquoise, Lapis, Malachite, etc. or pearls) in your jewelry do not use the liquid dips. I prefer these dips Tarn-X in particular for quick removal of a heavy tarnish as it will remove all blackness within seconds. I do not leave parts in any longer than necessary. Then a light rub with a polishing cloth puts on a nice shine as the chemical dips leave a dull finish. Polishing cloths are my second choice (or first if my jewelry has porous stones), the Sunshine cloths in particular are the best. They are not abrasive and remove tarnish without a lot of pressure and rubbing. A last resort is tarnish removing paste or polish as it is highly abrasive and would remove too much of the plating with each polishing.

My best advice though to extend the life of a plated item is too use techniques that minimize or slow down the build up or exposure to tarnish in between wearing. The less you have to polish the longer life your item will have. Store in plastic air tight zip lock bags with anti tarnish paper, anti-tarnish cloth jewelry bags, or at least in an air tight, low humidity environment. Do not place in a card board box or on paper as they have sulfur producing compounds in them that increase the rate of oxidation."

By Nancy Janeliunas of Janeluinas Jewelry

Brass

Brass is an alloy. That means two metals are melted and blended together to make a unique new property. In the case of brass, it's any alloy of copper and zinc.

On their own, copper will turn blue, green, or dark and tarnish rapidly. Zinc will also turn very dark. Together, they are much more resistant to tarnish. Brass itself will vary in color from a dark copperish gold to a bright yellow gold. Many people like it's golden appearance for jewelry. Brass is an inexpensive substitute for gold.

Like sterling silver, brass does tarnish, especially in great humidity or air pollution. Just use a soft cotton cloth to polish it to its original shine.

Plating adheres very well to brass, but it will slowly dull and fade away. How fast this occurs depends on the wearer's body chemistry, and the quality and humidity of the air. To help the plating last longer, do not use a jewelry cloth to polish the metal. Just use a soft cloth and wipe clean. Do not use any cleaners either. And the best way to keep the silver plating tarnish free is to store your jewelry piece in a zip lock bag that is airtight.

Pearls and Pearl Care

This is an article I have submitted to Ezine Articles to possibly be published on their website. Ezine Articles is a publication directory for articles on all sorts of topics. Just wanted to share what I was up to.

Classic white pearls are a must fashion accessory for every woman's wardrobe. They are so versatile that they can be worn for any formal affair to create an elegant look , or worn casually with jeans and a simple blouse. They are complimented nicely with sterling silver or gold, and combine well with an assortment of other gemstones. In nature, you can find pearls in shades of pink, brown or black. And now you can purchase pearls in an assortment of colors and finishes. Metallic finishes are currently very popular. They give pearls a brilliant shine and an iridescent look.

How a Pearl is Formed

A pearl is produced as a mollusk secretes layers of nacre or mother-of-pearl around an irritant. If the irritant is a natural grit or sand that makes it's way into the mollusk, the pearl is a natural pearl and is rare and expensive. If the irritant is placed inside the mollusk by human intervention, it is considered a cultured pearl. Layers of nacre gradually build up over years and form a spherical, oblong, or irregular shaped pearl depending on the original shape of the irritant. The thicker the nacre, the more durable the pearl.

Tips for How to Clean Pearls

Pearls are delicate and brittle no matter how thick the nacre. With proper care they can last between 100-150 years. The best way to clean pearls is:

* to dust them off and wipe them with a damp cloth.
* never clean them with harsh chemicals, including jewelry cleaners, or a sonic cleaner.
* take off your pearl jewelry when you apply make-up, perfume, or lotion on your hands
* if they do get dirty, they can be washed with a mild solution of soap and water.


The surface of a pearl can also scratch easily so how you store your pearls is important also. Try not to store them with other jewelry that may damage the surface.

Gold Jewelry Care

Over time, gold jewelry will get dull due to residue from lotions, soaps, oils, dirt, etc. If you are like me, it is important to keep your gold looking shiny and clean.

One way to clean gold jewelry is just with soap and warm water and a few drops of ammonia. With a soft toothbrush gently brush into the small crevices to remove the dirt and grime. When you are finished, rinse thoroughly with warm water.

You can also use a liquid type jeweler cleaner that is non-abrasive. These can be purchased any where precious jewelry is sold, and in some department stores as well. An ultrasonic cleaner is not recommended if your gold jewelry has any gemstones. Many gemstones are fragile and can be easily damaged

Be careful with chlorine. Remove all gold jewelry when swimming in a pool that uses chlorine. Chlorine can permanently discolor and damage you gold jewelry. Remove your jewelry when using detergents and other harsh household chemicals. They, too, can cause damage and discoloration to the metal.

How to Care for Your Sterling Silver Jewelry

Clean, untarnished sterling silver has a brilliance and shine that reflects light and enhances the beauty of any piece of jewelry. Gemstones look especially gorgeous when coupled with this shining metal. If you are at all like me, I don't like to have to clean my jewelry before wearing. I would like to share the quickest, easiest methods I have found to keep your silver jewelry shining, and cause the least amount of abrasion to your jewelry.

Tarnish on silver is caused by oxidation. The simplest explanation is that the metal becomes dull when exposed to air.  Using silver polish or a polishing cloth will actually scrub away at the surface of your metal, removing a layer of the silver.  Silver polish is also difficult to remove from small detailed areas of your jewelry.

One of the easiest methods is to keep your silver closed in seal able plastic bags. This is not the most convenient way to store your jewelry pieces, I know, but it is the best way. No-tarnish strips can be purchased at a jewelry supply company and will give add protection from oxidation if they are kept with your jewelry. Change these strips every couple of months for best results.

Probably easier to find would be chalk, basic chalkboard chalk. This can be used in place of the no-tarnish strips and will give you the same benefits. Basically the chalk absorbs any airborne substances that will tarnish your silver. Also change the chalk every couple of months.

Another method you can try is to line a glass baking dish with aluminum foil; place your sterling silver wire or jewelry pieces on the foil and cover it with a thin sprinkling of baking soda; add boiling hot water to cover the wire or jewelry; use a wooden chopstick or other non-metal utensil to gently stir the items around a bit so they all have contact with the aluminum foil at one time or another; when satisfied, remove the items and rinse thoroughly under tepid running water; pat items dry. For more stubborn tarnish you can also assist the cleaning process by using a soft toothbrush during the rinse process.

This method is not recommended to clean pieces that contain pearls, soft stones that have not been polished professionally, like turquoise, ivory, opals, or any precious stone that may have enhancements or treatments such as wax or oils, often used on sapphires, rubies and emeralds!

Another important rule about silver, and your fine jewelry in general, is to keep it away from harsh household chemicals such as bleach or chlorine.

I hope this information is helpful to all those silver lovers out there, like myself.

(These techniques are being shared from two articles, one by Rena Klingenberg, and the other by Dale “Cougar” Armstrong)