Pavilion
The pavilion is the lower cone of a diamond, below the girdle, that reflects light back up through the table.
The pavilion is the bottom section of a cut diamond, the cone that runs from the girdle down to the culet. It works like a set of mirrors, catching light that enters the top and reflecting it back up through the table to your eye. Its angle and depth are among the most important proportions in the whole stone.
How the pavilion returns light
Light enters through the crown and table, then strikes the pavilion facets. When the pavilion angle is correct, that light reflects off one facet to another and back out of the top, creating brilliance. This double reflection is why the pavilion is often described as a diamond's engine room. Get the angle right and the stone lights up; get it wrong and light escapes.
The pavilion angle sits in a narrow ideal window, close to 40.6 to 41 degrees for a round brilliant. Too shallow and light leaks out of the bottom, producing a dark centre or a glassy "fish-eye" look. Too deep and light escapes out of the side, making the stone look dark and lifeless. Even a fraction of a degree changes the result.
- The lower cone from girdle to culet
- Reflects light back up through the table
- Ideal pavilion angle is roughly 40.6 to 41 degrees for rounds
- Too shallow or too deep leaks light and dulls the stone
Pavilion depth and the cut grade
Pavilion angle and depth are central to how GIA grades cut, because they do more than almost any other proportion to decide light return. A grading report lists pavilion depth or angle among the measurements, so you can check it falls in the ideal range rather than trusting the overall cut letter alone. When people say cut is the most important C for sparkle, the pavilion is a big part of why.
- The pavilion is the lower cone of a diamond, below the girdle.
- It reflects light back up through the table like a set of mirrors.
- The ideal pavilion angle for a round is roughly 40.6 to 41 degrees.
- Too shallow or too deep and the diamond leaks light and looks dark.
- Pavilion angle and depth are central to the GIA cut grade.
Pavilion, in short.
What does the pavilion do in a diamond?
It reflects light that enters the top back up through the table to your eye, creating brilliance. The pavilion acts like a set of mirrors, which is why its angle is critical to sparkle.
What is the ideal pavilion angle?
For a round brilliant, roughly 40.6 to 41 degrees. Too shallow lets light leak out the bottom, giving a dark centre, while too deep lets it escape the sides, making the stone look lifeless.
Related terms
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