Here is a blue opalescent Hobnail small fan vase, made by Fenton during the 1940's and early 1950's. The pattern known as Hobnail features white hobnails on pale blue glass with a white ruffled edge at the top.
This fan-shaped blue opal glass vase is 4-inches wide by 1-inch deep on a 2-inch diameter foot. It is 4-1/8 inches tall, and would be perfect for violets or other small flowers.
Charmingly, It leans slightly to one side and needs some cleaning, but shows no damage.