Which term defines the angle formed by the pavilion mains and the girdle plane?

Which term defines the angle formed by the pavilion mains and the girdle plane?

• A. Pavilion depth percentage
• B. Pavilion angle
• C. Pavilion bulge
• D. Pattern

Answer: (B)

Pavilion angle describes the angle created where the pavilion mains—the main lower facets of the diamond—meet the girdle plane at the widest part of the stone. This angle determines how steeply the pavilion facets sit in relation to the girdle, which in turn affects how light is guided from the lower portion of the diamond back up through the crown and out the table. A proper pavilion angle helps maximize brightness and fire; if it’s too shallow or too deep, light can leak away and reduce perceived brilliance. Pavilion depth percentage, by contrast, is a measurement of how deep the pavilion is relative to the diameter, not the angle itself. Pavilion bulge isn’t a standard term in this context, and pattern refers to facet arrangement and symmetry, not the specific angle at the girdle.

Pavilion angle describes the angle created where the pavilion mains—the main lower facets of the diamond—meet the girdle plane at the widest part of the stone. This angle determines how steeply the pavilion facets sit in relation to the girdle, which in turn affects how light is guided from the lower portion of the diamond back up through the crown and out the table. A proper pavilion angle helps maximize brightness and fire; if it’s too shallow or too deep, light can leak away and reduce perceived brilliance.

Pavilion depth percentage, by contrast, is a measurement of how deep the pavilion is relative to the diameter, not the angle itself. Pavilion bulge isn’t a standard term in this context, and pattern refers to facet arrangement and symmetry, not the specific angle at the girdle.