Chelsea Filter, Dichroscope, Jewelers Loupe, Gemological Refractometer - Gem Identification Tools, Bundle 6 Items Chelsea Filter - now used to identify mostly any gemstone Dichroscope - invaluable for distinguishing certain stones from similar gems. 10x triplet jewelers loupe in black housing-one of the most important gemstone identification tools. Quality Gemological Refractomer with 10 grams of Certified RI. 1.80 Liquid included. BONUS - GEMSTONES OF THE WORLD book by Walter Schumann.