William Holland Lapidary School - July 2007 Opal Class << Previous   Next >> Introduction William Holland Lapidary School - Topics of Interest Opal Class << Previous Introduction Next >> Introduction Accommodations ClassRooms Show & Tell Auction Night Opal Class Gem ID Class Gem Identification Tools REFRACTIVE INDEX LIQUID 1.81 Faceting Rough 15 ct Lot of Oxblood CitrineA Grade Gem Scales & Filters PR Digital Carat Scale 100ct x .01ct Click any text above for more information