Natural Pearl Identification

by kashif
(lahore, pakistan)

I have a family ring with a pearl mounted on it as seen in the picture. Although i have other ways of identifying this pearl by getting it verified by any laboratory but i find this a more easy way to verify it as a natural pearl. what i want to know from your great experience is that by taking a glance at these pictures what do you think, is this a natural pearl or instead a cultured pearl?