How to measure gemstones

Table of Contents

How to measure popular gems used in jewelry.

Below is a pictorial guide on measuring the most popular
gem stone shapes used in jewelry. Gem shapes depict
faceted cuts but gems cut cabochon and buff top are
measured the same way as the faceted stones.


Round-Shaped Stones
Measured across the widest part.


Oval-Shaped Stones
Measured vertically from the top to the bottom, and
across the widest part.


Pear-Shaped Stones
Measured vertically from the top to the point, and
across the widest part.


Octagon-Shaped Stones
Measured vertically from the top to the bottom, and
across the widest part.


Heart-Shaped Stones
Measured vertically from the top to the bottom, and
across the widest part.


Square-Shaped Stones
Measured vertically from the top to the bottom, and
across the widest part.


Baguette-Shaped Stones
Measured vertically from the top to the bottom, and
across the widest part on straights, or both end
widths on tapers.
See emerald or princess cut for straight baguette.


Triangle-Shaped Stones
Measured vertically from the top to the point.


Marquise-Shaped Stones
Measured from the top point to the bottom point, and
across the widest part.