This is a lovely Chrysocolla ring in a contemporary style. The silver has been textured and oxidized to bring out the design. The underside is stamped with the hallmark and marker's mark.
The measurements of the top of the ring is 1-1/4-inches by 1-inch. This band is not very wide.
For wider bands, you usually need about 1/4 size or more larger if the band is very wide.