Gemstone collecting was made an art as well as a science by the late Dr. Eduard J. Gubelin, affectionately known in the industry as "gemstone royalty" because of his world-class gem collection, his pioneering research and his charming, gentlemanly ways.Simply stated, shape is the outline or form that any gemstone exhibits when viewed face up. Examples of commonly seen gemstone shapes include square, rectangle, round, triangle, octagonal (square or rectangular), cushion (square or rectangular), pear, heart, marquise and oval.