Antique/Vintage Sterling Los Castillo Screwback Signed Earrings

Storage find.This is a vintage/antique pair of sterling silver Los Castillo screwback earrings.I believe stones are turquoise.I can barely make out writings."Sterling,made in Mexico,Los Castillo,there's a number appears to be 380,a letter,"D".There's a mark or a figure in the middle of one earrings,I can't make it out.One of the screwback is bent a little,I didn't try to straighten it out for fear of damage.Both screw up and down.Earrings need a good cleaning. los Castillo is the first family of Taxco. Originally with Spratling, but soon out on their own, they became innovators of Sterling Design, Mixed Metals and Ceramics with Pure Silver Overlay. Don Antonio Castillo headed his Taller, Los Castillo, until his recent passing. The Los Castillo Shop is located at the Estate of Antonio Castillo, the Rancho de la Cascada, surrounded by gardens, waterfalls and ancient artifacts. Until his recent passing, Don Antonio continued his innovations in Silver Art with new works in amber, carved stones and his dynamic settings of pre-Columbian ancient artifacts, of which he was a world renowned expert and collector. Don Antonio passed away on May 25, 2000. Taxco Lost a Legend. Under family members, the Los Castillo Taller continues to operate with it's exploration and innovations in Silver and other Materials in wonderful new designs.