Woodbridge Antiques has dated this piece to the 1920s.

A sublime ring, wonderful for a collector of antique jewellery,
Condition: In great antique collector's condition
Hallmarks: Birmingham 1917
Measurements:
Ring size N
Amethyst stone including setting: 1 cm approx x 8.6 mm approx.
Width measurement shoulder to shoulder inc pearls: 1.7 cm approx.
Width of band at base: 1.9 mm approx.
Weight: 2.7 grams approx.
Woodbridge Antiques has dated this piece to the 1920s.
Specialists in quality antique silver, fine jewellery & accessories
You can view the stock and full dealer information on the Woodbridge Antiques Profile Page