Very Rare Find - Black & Clear Statement Brooch Rhinestone Brooch - stamp 2”X 2”

Love this brooch but the listing is wanting in information. Obvious clear rhinestones that look like diamonds. Black Jet colour stones that may be rhinestone, black Alaskan or jet. A simple stunning adornment. Well made vintage 4 prong setting. Has a stamp be nearly indecipherable ( possibly CB). Minimal wear - well preserved condition.