Thank you for submitting your item for appraisal. The ring appears to be in white metal with a central blue stone. The item seems in sterling silver (925) and its diameter is 2.5 cm. The stone set in the center of the ring is oval shaped, it measures 6x4mm, it is vivid medium blue color. Observing the photos it is not possible to determine if it is natural or synthetic. According to the pictures the ring is modern.
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