by Bob Keller, Old Pueblo Lapidary Club I learned to facet on a Facetron in an Old Pueblo Lapidary Club faceting class. I also worked in class on an Imperial outfitted with a dial indicator. The machine that’s been may favorite for several years now is …

by Bob Keller Fundamental Concepts You will often encounter the terms refractive index and critical angle employed in faceting related discussions. Understanding these terms and how they relate to the optical properties of gemstones and different gem m …