Silver ring with turquoise stone, vintage

A beautiful sturdy crafted silver ring with a turquoise round stone. The so-called Eilat stone, this is a combination of turquois, chrysocolla, malachite and azurite. The Eilat Stone is of course named after Eilat, the first location of the stone. The vintage silver ring is marked ZZ on the outside and on the inside of the stone with 925 and another mark on the inner edge, which is unfortunately too vague to decipher. The vintage ring was made in Israel and is in good condition.