Plastic Fan Shaped Ring Sizer British Standard J to Y

Holes are used to measure stones and extensions are used to measure mountings.
Gauge has mm and carat measurements.

Nickel plated steel with roller adjustment. One edge is
graduated in inches reading ½” in ½” in 1/16” divisions and other
edge in metric scale from 0 to 120mm in 1mm divisions.

K&B Diamond and Stone Gauge.
Measures loose or mounted stones from 3 points to 4 carats.
Birthstone chart on reverse.