This is an Edwardian setting of 20K white gold. It has two full cut genuine Diamonds and a large loaf cut Blue Stone. It is size 5.25 and could be sized by your local jeweler. It weighs 5 grams which is impressive for a ring of that size,
It is in excellent estate condition and the fact that the center tone is synthetic was the fashion for much of jewelry of this time. Really pretty detail work and such a lovely shade of blue. No one need know it is not earth mined.