Weight estimation is a critical step in assessing the value of a mounted diamond. If the stone is loose, you could simply put it on your scale and consistently obtain an accurate weight . In dealing with mounted diamonds, this is not a luxury that you will always have. Many times the seller will allow the stone to be removed from the mounting for the purposes of weighing and grading. If not, you must take measurements and formulate an estimated weight for the stone. In some mountings, this will be relatively easy, but in others, it will be impossible.