• Select Emeralds, Rubies, and Sapphires

• Evaluate Gemstone Color

• Buy Birthstones

• Maintain Your Gemstones

• Find Gemstones on eBay

• Buy Gemstones with Confidence

Select Emeralds, Rubies, and Sapphires

Select Emeralds, Rubies, and Sapphires

The three most widely-recognized non-diamond gemstones, sapphires, rubies, and emeralds, typically have some mineral traces or inclusions. You'll have a hard time finding rare (and very expensive) slightly-included or flawless gems. But you shouldn't worry too much; the jewelry industry considers even moderately-included gems "desirable."

• Emeralds: Emerald hues range from yellow-green to blue-green. The most valuable stones are pure green. Considered the birthstone of the month of May, emeralds are also the anniversary gemstone of the 20th, 35th and 55th year of marriage. Emeralds lend themselves to elaborate carving and inscription because of their composition.

• Rubies: Traditionally considered the most valuable gemstone, rubies are the birthstone for the month of July and traditional 15th and 40th year anniversary presents. Ruby hues range between orange-red and purple-red. 

• Sapphires: Sapphires represent September birthdays a well as 5th and 45th wedding anniversaries. Hue ranges from blue-green to blue-purple, but sapphires also come in many other colors including colorless, white, yellow, orange, pink, brown, and black.

Rubies, emeralds, and sapphires usually undergo treatments to enhance color and fill cracks. The jewelry industry considers treatment of these three gemstones standard practice.    

• Oil & resin gemstone treatments: Gemstones, like emeralds and rubies, are frequently treated with oils and resins. Time and excessive heat can cause this filler to break down, requiring the gems to be professionally repaired.

• Gemstone heat treatment: Sapphires and rubies frequently are treated with heat. This process permanently enhances color without changing the stone's structure. 

• Chemical or "diffusion treatment" for gemstones: On a less frequent basis, gems can be treated with cobalt, beryllium or other elements to enhance apparent color. However, this only changes the surface of the stone. A scratch can reveal the lighter hue underneath.

Most eBay sellers will provide details about any treatment applied to their gemstones. If they don't, request the details before bidding on the item.

Evaluate Gemstone Color

Evaluate Gemstone Color

When shopping for gemstones pay close attention to color. Unlike diamonds, different gemstones have different densities, rendering carat weight useless as an accurate measurement of size (to determine size, look at diameter, length, and width measured in millimeters). In other words, a lighter weight gem with even color may be more valuable than a heavier gem. Also, the color of good stones can mask inclusions more than in diamonds. You should look for three aspects of color:

• Hue: Hue is the unique color of the gemstone. While almost all stones have some shades of other colors, the most valuable stones present the purest hue: red rubies, green emeralds and either blue or pink sapphires.

• Tone: Tone is the depth of a gemstone color, from colorless to black. Tone is described on a scale that ranges from light to medium to dark. The most valuable stones range from medium-light to medium-dark

• Saturation: Saturation is the purity of the color throughout the gemstone. A gem that is free of gray or brown hues is said to be strongly saturated and is more valuable than a stone with lower saturation. Saturation often determines the cut of a gemstone. A high-quality gem cut delivers an even color throughout the stone and exposes the fewest inclusions.

Stones with a deep, saturated color look best and are most valuable with a shallow cut that allows consistent, bright color. A stone with less color saturation should be cut more deeply to let more light into the stone for sparkle. Symmetry (the balance of the gem's facets) and polish (the surface smoothness of a gem) also affect the sparkle of the gem and can enhance or detract from its value.

Buy Birthstones

Buy Birthstones

For birthday gifts, you may want to consider buying jewelry that includes a person's birthstone.

Maintain Your Gemstones

Maintain Your Gemstones

Make sure your gemstones stay in tip-top shape with a few simple steps. Jewels need space to remain free of chips. Store gems individually in soft cloth pouches and prevent jewels from bumping against one another.

Clean your gemstones

Dust, skin oil and other unclean substances can cause your diamond or gems to lose their sparkle. Clean your gems from time to time in soap and water. Air dry and polish with a soft cloth. Occasional brushing with a worn, soft-bristled toothbrush can help remove dirt from between crevices. Remember to treat metal settings gently; gold can scratch. For more resistant blemishes, use a weak solution of ammonia and water (about one part to four parts) and a soft brush.

Take your gemstones to the jeweler

Annual checkups with a jeweler help keep your gemstones clean and properly situated in their settings. A jeweler can clean gems with steam or ultrasound, though ultrasound can make internal fissures or flaws worse.

Although four-prong, six-prong, and low-profile channel or bezel settings offer your gemstone more protection than other settings, you should ask your jeweler to make sure your gemstones are still sitting tight in their settings to help prevent stones from falling out.

Find Gemstones on eBay

Find Gemstones on eBay

Once you know what type of gemstones you want, go to the Jewelry & Watches portal and enter the name of the gemstone you want to find into the Search box. For example, if you want to find emeralds, type "emerald" (without quotation marks into the Search box. Click "Search title and description" to expand your results. (Visit eBay's Search Tips page for more tips on searching with keywords.) Use the Categories lists o the left side of each page to narrow down your listings by item type.

If you can't find exactly what you want, try shopping eBay Stores, tell the eBay Community what you want by creating a post on Want It Now, or save a search on My eBay and eBay will email you when a match becomes available.

Buy Gemstones with Confidence

Buy Gemstones with Confidence

Before making your purchase, make sure you know exactly what you're buying, research your seller, and understand how eBay and PayPal protect you.

Know your purchase

Carefully read the details in item listings.

• Figure delivery costs into your final price. If you spend a lot of money, make sure the seller will insure the item when it ships.

• If you want more information, ask by clicking the "Ask seller a question" link under the seller's profile.

• Always make sure to complete your transaction on eBay (with a bid, Buy It Now, or Best Offer). Transactions conducted outside of eBay are not covered by eBay protection programs.

• Never pay for your eBay item using instant cash wire transfer services through Western Union or MoneyGram. These payment methods are unsafe when paying someone you do not know.

Know your seller

Research your seller so you feel positive and secure about every transaction.

• What is the seller's Feedback rating? How many transactions have they completed? What percentage of positive responses do they have?

• What do buyers say in their Feedback? Did the seller receive praise?

• Most top eBay sellers operate like retail stores and have return policies. Do they offer a money-back guarantee? What are the terms and conditions?

Buyer protection

In the unlikely event that a problem arises during your transaction, eBay and PayPal are there for you.

• Pay safely with PayPal: PayPal enables you to pay without the seller ever seeing your bank account or credit card numbers. In fact, PayPal protects buyers 100% against unauthorized payments from their accounts. Plus, with PayPal Buyer Protection, your purchase can be covered up to $1,000.

• eBay Security & Resolution Center: Visit the Security & Resolution Center to learn how to protect your account and use eBay's quick and efficient resolution tools.