Diamond and Gemstone Analysis
When it comes to the quality of your gemstones, you want a professional that pays attention to every detail.
With over 30 years of experience assessing diamonds and gemstones, our GIA certified graduate gemologists have seen it all!
Feel free to bring in any size diamond, emerald, ruby, sapphire, or other gemstones. You’ll see our attention to detail is incomparable, and our knowledge of the gemstone market allows U.S. Coins & Jewelry to get you the most cash for your stones.

Understanding GemstonesGemstones such as rubies, sapphires, and emeralds are naturally occurring mineral crystals that have been cut and then polished. Since ancient times, gemstones and the jewelry they adorn have been a part of human society. Throughout history, gemstones and jewelry have been used for signifying wealth and status. Today, global urbanization means that the popularity of gemstones continues to increase. With the emergence of wealthy middle classes in rapidly growing economies, there is a huge demand for gemstones, but regulation has struggled to keep up with this demand. As a result, the sale of fraudulent and fake gemstones has skyrocketed, and there is a need for an effective and fast way of determining authenticity. Our team is trained to evaluate stones. | How are Gemstones Identified?Gemologists make use of tools including jeweler’s microscopes, loupes, or measurement of the refractive index in order to identify synthetic gemstones or those that have been improved. A jeweler’s loupe is a magnifying device that allows inclusions and blemishes to be seen. Microscopes offer further magnification and can be employed for detecting heat treatments and various other clarity enhancements. However, these techniques all need a trained gemologist to perform the analysis, and the decision always includes human error. Furthermore, synthetic gems and enhancements are becoming immensely sophisticated, making standard methods unreliable. As a result, sophisticated methods of gemstone analysis, which are borrowed from analytical chemistry, are indeed becoming popular. |
The price of gems relies on their identity, color, clarity, weight (carat), size, origin, shape, treatments, cut, and polish. Some of the rarest gemstones, such as the red diamond, are capable of fetching up to $1 million per carat.
Considering Selling Your Diamonds, Rubies, Sapphires, and Emeralds?
We are Houston’s most trusted source and will match or beat any reasonable offer. Just bring it in, and we will be happy to get you a free appraisal.
Call us at (713) 597-6367 or visit our retail store.
We buy all large GIA Diamonds and Gemstones including Rubies, Sapphires, and Emeralds.
Call us today at (713) 597-6367 or fill out the form for a free quote.
How much should you ask for your item?
If you do not know how much money you should be asking for your item, you should get a fair market value appraisal from a trusted appraisal company. U.S. Coins and Jewelry offers free no-obligation appraisals. A trained appraiser will take into consideration the various factors that go into pricing: the quality of the gemstones or the jewelry, availability on the market, and desirability for that particular stone or piece of jewelry in your area.
Fair market value will give you a baseline price, to help you decide how much to ask for the stone or jewelry piece.
Helpful tips for selling a gemstone or jewelry
Whether it’s a piece of heirloom diamond jewelry or a loose colored gemstone found in the bottom of your jewelry box, these commonly asked questions will help you sell your gemstones or jewelry with ease.
Are there such things as GIA-certified appraisers?GIA does not certify appraisers. GIA teaches students how to identify gemstones and grade diamonds, but they do not teach them how to write appraisals. An appraisal is a legal document, and an appraiser should have specialized training in this area. At U.S. Coins and Jewelry, we have appraisers on staff who will carefully examine the condition and quality of your gemstone. Our company has been buying and selling gemstones for over 30 years, and we have generations of happy customers who received great value for their gemstone and a great experience. | What do I do after the appraisal?After you have your appraisal completed, talk to the appraiser about their interest in purchasing your item. Many gemstone buyers buy low and sell it cheaper because they want to churn through as many transactions as possible. At U.S. Coins and Jewelry, we deliver one-on-one customer service, and we want to build an inventory of quality gemstones to sell to our customers. That means we can pay much more than a typical “Cash for Gemstones” operation. |