Jewelry Appraisal Info


Gemstone Care

Jewelry Care

San Diego Gemological Lab is fully equipped. We are a Certified Laboratory of the Accredited Gemologists Association. Mr. Underwood earned & maintains the highest jewelry appraiser credentials in three professional appraisal and gemological organizations.

  • American Society of Appraisers (ASA)
  • National Association of Jewelry Appraisers (NAJA)
  • Gemmological Association of Great Britain (FGA)

We do not buy or sell jewelry, gemstones or precious metals. You will receive a truly unbiased appraisal. The appraisal is performed in accordance with the high standards of the Uniform Standards of Professional Appraisal Practice (USPAP), the American Society of Appraisers, & the National Association of Jewelry Appraisers. More details about jewelry appraisals...

Fine Jewelry Care

Get into the habit of removing your jewelry before showering or bathing. (This is a good time to carry out its daily cleaning.) Soap can deposit a film that diminishes the liveliness and beauty of your jewelry, necessitating more frequent cleaning. Also remove jewelry before putting on makeup or powder or hair spray, and wash your hands to remove dulling residues after applying makeup before handling your jewelry.

Try not to touch the stones in your rings when putting them on or off. Instead, hold the ring by the shank (metal portion that encircles the finger). Touching the stones will cause a greasy buildup on their surfaces, which greatly reduces brilliance and sparkle.

To restore rings' sparkle, get into the habit of "huffing" them to remove the dirt and oily film on the stone's surface. Simply hold the ring close to your mouth, "huff" on it with your breath - you'll see the stone fog up - and wipe it off with a soft, lint-free cloth such as a handkerchief or a blouse sleeve. You'll be amazed to see how much better jewelry can look simply by removing even the lightest oil from the surface!

Don't take off rings and lay them on the side of the sink unless you are sure the drain is closed. Also, never remove your rings to wash your hands when you are away from home (unless you hold them in your teeth!); all too many have been forgotten and lost. Never wrap your jewelry in facial tissue, which might later be tossed into the trash!

Avoid wearing fine jewelry while doing any type of rough work, such as house cleaning or gardening. Abrasives can scratch your jewelry - both the stones and the metal. Chemicals such as chlorine can cause discoloration of metals used in settings and dull the polish on many stones, making it necessary to have the stone re-polished to restore its full beauty. Chlorine can also cause pitting and discoloration to settings. Ammonia will remove the polish on soft, porous stones such as malachite, turquoise and coral.

Avoid exposing fine jewelry to intense heat, for example, while cooking. Exposure to extreme heat can cause damage to many gems. Enamel also may be ruined by contact with heat.

Every 12 to 18 months have your jeweler check each piece to make sure the setting is secure, and have prongs or shanks reinforced as necessary. If you ever feel or hear the stone moving in the setting, it is a warning that the prongs or bezel need tightening. Also, check catches and clasps to make sure they are secure and working properly. Failure to take care of this may result in loss or damage.

Storing Your Fine Jewelry

Avoid exposing fine jewelry to extreme temperature changes, such as might be encountered by putting jewelry in a refrigerator or in-the-ground safe during the winter, where temperatures may be quite cold, then removing it and wearing it in a heated room. This is especially true with opals.

Store your jewelry in a dry place. Avoid extremes of temperature and humidity. Keep gemstone-studded jewelry, pearls, and gold jewelry separated from each other to prevent scratching. Store silver separately from gold jewelry, to avoid tarnishing the gold. Do not store pearls or opals for long periods of time in a safe deposit box. The dry, close air and dark environment seems to discolor pearls and dry out both pearls and opals. Keep fine jewelry in soft pouches or wrapped in soft cloth to help protect it. Don't overcrowd your jewelry box. This can result in misplacing or losing pieces that might fall unnoticed from the case, or damage, such as bending a fragile piece or chipping a fragile stone.

Diamonds can scratch other gemstones very easily, and can also scratch each other. Ideally, to prevent scratching, diamond jewelry should be placed in a case that has dividers or separated compartments, or each piece should be individually wrapped (but not in facial tissue).

Pearls of all kinds (natural, cultured, South Sea, Tahitian, freshwater) are very soft, only 2 to 4 on the Mohs hardness scale. Because normal dust contains much harder quartz particles, pearls can be easily scratched if left uncovered. Store pearls in a separate pouch, preferably one lined with a soft fabric such as satin, or wrap it to prevent scratching the pearl's surface on sharp metal edges or prongs, or against harder stones. Never toss carelessly into a purse or travel case. Avoid contact with ammonia, inks, hair spray, perfumes, cosmetics, and especially vinegar, which will immediately begin eating the pearl's surface. These substances will spot the pearls, and some of the substances may weaken the string, making it susceptible to breakage.

Restring pearls periodically. If they are worn frequently, once a year is recommended. Fine pearls should always be strung with knots tied in the space separating each pearl to prevent them from rubbing against each other (which can damage the nacre), or from scattering and getting lost if the string should break. Treat any organic gem, such as amber, coral or jet as you would pearls.

How To Clean Your Fine Jewelry

Perhaps the simplest and easiest way to clean any kind of jewelry is to prepare a small bowl of warm, sudsy water, using any kind of mild liquid detergent. Let the piece soak a few minutes and then brush gently with a soft complexion brush or soft-bristled toothbrush, keeping the piece submerged in the sudsy water. Rinse thoroughly under running water (make sure the drain is closed; some prefer to place the jewelry in a strainer before putting it under the running water) and pat dry with a soft, lint-free cloth or paper towel.

For karat gold jewelry without gemstones, rubbing with a soft chamois cloth will restore much of the luster. Tarnish can be removed with a solution of soap and water to which a few teaspoons of ammonia has been added. Using a soft toothbrush, brush the jewelry with this solution, rinse with warm water and dry with a soft cloth. Grease can be removed by dipping in plain rubbing alcohol before washing.

Never clean opals or emeralds in an ultrasonic cleaner. They can crack opals, and remove oil treatments from emeralds, making inclusions more visible and weaken the apparent color.

For more detailed jewelry cleaning information, go see our Gem Care Chart.

Precautions While Traveling

If you take jewelry with you when traveling, don't pack it in luggage (such as an overnight or makeup case) to be given to the bell captain at a hotel, ship's porters, etc. Never leave it in your room. Wherever possible, obtain a safety deposit box in which to store your jewelry when not wearing it, even for part of a day. Also store the jewelry you leave behind at home in a safety deposit box.

Never remove your jewelry and wrap it in a facial tissue - many pieces have been thrown away accidentally this way. Keep a small pouch handy in your purse.

Purchase a "body pouch" that can be concealed under clothing for when you must carry a valuable piece.

Never go sightseeing with valuables in a purse or pocket.

For customs purposes, it can be useful to take a photocopy of your jewelry appraisal with you. Or, have a photo of the jewelry that is dated and notarized prior to departure and keep it in your passport. San Diego Gemological Laboratory can take enlarged color photographs of your jewelry for this purpose.

Enjoy Your Fine Jewelry!

Your jewelry is an intimate expression of your personality and a sentimental reminder of important occasions. It will last a lifetime if properly cared for. Keep your favorite pieces in mind when you make additions to your wardrobe! Wear your jewelry. Enjoy it! And give it the care befitting the precious material that it is.

Want to Know More?

The above information was written by Nancy Stacey GG, ISA-CAPP, ASA Master Gemologist Appraiser® and based in large part on an article written by Antoinette Matlins, internationally respected gemologist and consumer advocate, and fellow AGA member. You have probably seen her spirited discussions on ABC, CBS, NBC and CNN. Antoinette has published several excellent books that would be of interest to anyone seeking a more in-depth knowledge of gems and jewelry.

  • Jewelry and Gems: The Buying Guide, 4th Edition - How to buy diamonds, pearls, colored gemstones, and gold jewelry with confidence and knowledge.
  • The Pearl Book: The Definitive Buying Guide - How to select, buy, care for and enjoy pearls.
  • Engagement and Wedding Rings, 2nd Edition: The Definitive Buying Guide for People in Love - Takes the anxiety out of buying engagement and wedding rings, turning it into the magical and romantic experience it should be.
  • Gem Identification Made Easy, 2nd Edition: A hands-on guide to more confident buying and selling - Explains what instruments are needed, how to use them, where to get them, and what should be seen for each gemstone.

To order, contact: Gemstone Press, http://www.gemstonepress.com.