1. There are other factors which can affect a diamond’s value other than the 4 C’s (cut, color, clarity, and carat). One such factor is florescence.  Florescence is the blue hue which a diamond can exhibit after being exposed to sunlight.  High florescence can be detrimental to a diamond’s value.
  2. It is vital to have a gemological certificate when selling a fancy colored diamond.  This is the only way for a buyer to have 100% confidence that the diamond’s color is natural rather than the result of having been treated.
  3. Square or rectangular cut diamonds have a tendency to chip in the corners when mounted. This is why it is important for a buyer to see square or rectangular cut diamonds outside of their mountings.
  4. Due to advancements in diamond cutting techniques, old diamonds or diamond estate pieces often require re-cutting before they can be sold in today’s market.
  5. The culet is a small flat surface cut into the underside of a diamond in order to prevent chipping.  When a culet is so large that it becomes noticeable, it will negatively affect a diamonds value.
  6. GIA certificates are the industry standard and the only diamond certificate that is indisputable. Other laboratories are more lenient in their grading standards.  It is possible that a diamond graded G color by GIA would receive an E or F grade from another lab.
  7. GIA is a nonprofit organization formed to protect the public.  They are a completely reliable source of information and grading in regards to diamonds and gems.
  8. If a buyer tells you the diamonds in your ring have no value, ask him to extract them for you after he makes his offer.
  9. You can inspect a diamond for inclusions yourself.  All you need is a loupe or magnifying glass which produces 10X magnification.  If you are able to see any inclusions easily, your diamonds clarity grade is most likely SI1 or lower.
  10. Diamonds always have value, no matter how small or poor in quality.  If they are not suitable for jewelry, they have many industrial applications.
  11. Invisible set diamonds look pretty but can be very difficult to resell.  In order to stay in place, grooves are cut into them so they fit into each other like a puzzle.  They only have value in the piece and can’t be sold as loose diamonds without first being re-cut to remove the grooves.
  12. Very few buyers have the knowledge required to pay high levels for diamonds. As a result, they will pay way below market value in order to ensure their profits.  Make sure the buyer you select is a certified gemologist with a history dealing with diamonds.
  13. Diamonds never show signs of age and are extremely durable.  Sometimes all a diamond needs is to be re-polished in order to regain its original luster and brilliance.
  14. The brilliance and fire a diamond exudes vary from diamond to diamond and can have a large affect on its value and marketability.
  15. Inclusions which are in the center of a diamond have a greater effect on its resale value then those which are off to the side.  This is because they are much more visible to clients and can’t be covered by prongs in a mounting.
  16. GIA certificates contain all of the necessary information for a buyer to make an offer on a diamond.
  17. Information on diamonds is readily available all over the internet.  You can use what you find to get a better understanding of your diamond. This will allow you to make an informed sale decision.
  18. Loupes are inexpensive and can be purchased online or from jewelers supply stores around the country.  They are the same tool diamond graders use to inspect diamonds. By self inspecting your diamonds with a loupe, you can get a fairly accurate impression of their quality.
  19. You can look up your diamonds certificate on GIA’s website by inserting the GIA report # and the diamond’s carat weight.
  20. Some diamond sizes demand a premium price as a result of current market trends and demand.
  21. Fancy shape diamonds tend to go in and out of style over time.  Whether or not they are in style can have a large effect on their value.
  22. Diamond prices are like stocks in that they fluctuate as a result of market changes.  These fluctuations relate to the international supply of and demand for diamonds.
  23. The cut of a diamond is very important in determining its value.  A poorly cut 2 carat diamond can have less value then a 1.50 with the same color and clarity grade.
  24. Members of the public are able to certify their diamonds themselves by sending them into certifications laboratories.  The price for certification varies by lab and the size of the diamond.
  25. Diamonds can get scratches or even burns over time.  This makes them appear to be lower in quality.  Burns and light surface scratches can be repaired by a diamond polisher.
  26. Large 1ct plus size diamonds should be sold to buyers who specialize in buying diamonds.  Diamond grading is a trade which takes years to master and a buyer without the proper experience will be reluctant to pay high out of fear that he may be incorrectly grading the diamond.
  27. Try to get as much information from a potential diamond buyer as possible.  The information they give you can help you be better informed on the characteristics of your diamond and its worth.
  28. A good buyer may insist he be able to remove any large diamonds from their mounting before making his offer. This is because a diamond may have inclusions, chips or color defects which are hidden by the mounting.
  29. Gold buyers specialize in buying gold, not diamonds.  They pay low fixed rates for diamonds which greatly undervalue their worth.