The construction of the mounting does not permit the refractometer to be used. The tremendous value of the spectroscope as an analytical tool lies in its ability to save time in gem testing, by providing initial identification of many gems, with the microscope being the only other tool required.įor example, let’s say you are given a dark blue transparent stone set in a closed back mounting. But, like any weapon, you hit little if you depend on luck alone. The spectroscope is one of the most powerful instruments in a gemologist’s quiver. This fear factor leads students into a self-fulfilling cul-de-sac where lack of skill leads to lack of success and the eventual conclusion that the spectroscope is of little use. Among these, the direct-vision spectroscope is generally the most difficult to initially master.

Of primary importance are the microscope, refractometer, ultraviolet light, specific gravity equipment, and the spectroscope. Gem testing laboratories make use of a variety of instruments, both high-brow and low. Many gemologists have difficulty mastering the direct-vision spectroscope.

Ruby and blue sapphire together