a polished ring with a lustrous blue gem

The ring is round and perfectly shaped to fit around a finger. Only a small marking can be found on the inside of the ring, a signature of the silversmith that forged it. The top of the ring features a square, silver setting with room for a gem. The ring has been embedded with a lustrous opal.

It is a polished ring with a lustrous blue gem.
It weighs a few ounces.

You identify a polished ring with a lustrous blue gem.
It is an anti-summoning object. It is efficient against long range spells.
It weighs three ounces, and it is worth about eleven gold, seventeen silver, and fifty copper.
Its keywords are ring, polished, lustrousblue-ring, lustrous, and blue.