During the 1940s Hector Aguilar was contracted to Coro to design and make sterling jewelry. This orchid brooch was one. 3 3/4" by 2 3/4" with sturdy safety clasp. Marked Made in Mexico, Coro in script, and silver in a circle. Acid tested as 925 or better. I have added a sterling neck ring (fits a 16 to 18" neck and is 4mm wide) and a sterling brooch converter. All pieces can be used separately. The mention of the relationship between Coro and Aguilar is mentioned in Morrill and Berk, ed 3. page 101. Excellent vintage condition.