Elegant 1930's Art Deco 18k White Gold Natural Diamond Synthetic Ruby Engagement Ring To Restore

This lovely art deco natural diamond engagement ring was crafted from 18k white gold (stamped "18k"). It features a center natural round old lumpy cut diamond weighing ~1/4ct. The diamond is VS in clarity and H-I in color. It is accented with one synthetic ruby. One synthetic ruby is missing. It measures 8.8mm lengthwise on top of finger. Ring size is 4.5. It weighs 2.5 grams.