Which term refers to a well-shaped, transparent, octahedral diamond crystal with sharp, square edges?

Which term refers to a well-shaped, transparent, octahedral diamond crystal with sharp, square edges?

• A. Girdle thickness percentage
• B. Glassie
• C. Gravity sorting
• D. Graphitization

Answer: (B)

The key idea here is crystal form and surface quality. A well-formed octahedral diamond crystal with clear, transparent faces and crisp, sharp edges is described as glassie. The term highlights two things: the octahedral crystal habit (the shape is formed by well-developed crystal faces) and a glassy, bright appearance that shows excellent luster and minimal surface flaws. This combination signals a high-quality rough diamond, where the crystal integrity and surface condition are favorable for cutting and brilliance. Girdle thickness percentage, gravity sorting, and graphitization relate to other aspects of diamond evaluation and processing. Girdle thickness describes how thick the diamond’s girdle is, not its crystal shape. Gravity sorting uses density to separate stones, not the crystal form. Graphitization is a deterioration process where diamond is converted to graphite, which harms transparency. These concepts don’t describe the crystal’s shape or edge quality the way glassie does.

The key idea here is crystal form and surface quality. A well-formed octahedral diamond crystal with clear, transparent faces and crisp, sharp edges is described as glassie. The term highlights two things: the octahedral crystal habit (the shape is formed by well-developed crystal faces) and a glassy, bright appearance that shows excellent luster and minimal surface flaws. This combination signals a high-quality rough diamond, where the crystal integrity and surface condition are favorable for cutting and brilliance.

Girdle thickness percentage, gravity sorting, and graphitization relate to other aspects of diamond evaluation and processing. Girdle thickness describes how thick the diamond’s girdle is, not its crystal shape. Gravity sorting uses density to separate stones, not the crystal form. Graphitization is a deterioration process where diamond is converted to graphite, which harms transparency. These concepts don’t describe the crystal’s shape or edge quality the way glassie does.