I purchased these at a moving sale of a lady who was a military baby born in Turkey. She said that her parents brought these back from their time in Turkey. So these are at least 70 years old.

Vintage Turkish Onyx & cast Metal Dolphin Candlestick Holders - Ornate Pair
Description:
Design: These elegant candlesticks feature highly stylized cast Metal made to resemble brass dolphin (or "koi fish") stems, a classic nautical motif often found in Hollywood Regency and Turkish decor.
Materials: Each piece is constructed with a solid, polished onyx marble base and matching onyx bobeche (top wax catcher), joined by an ornate cast Metal imitation brass dolphin stem.
Style: Late 20th Century / Vintage Hollywood Regency.
Condition: In good vintage condition with natural patina on the brass. The onyx bases show the natural swirls and bands characteristic of genuine stone.
Measurements: Approx 5-3/4” tall.