This is a very pretty vintage art deco style 10K and rolled black onyx ring. It was made by the HACO company which opened its doors in the early 1960s. It measures as a size 8, and the onyx stone is approximately 3/4 of an inch by half inch. It is marked 10K and has the makers mark. It is in very nice vintage condition and ready to wear.
Please note I only use natural daylight to take photos, and they are never enhanced. I may zoom in on the item to show detail. I do not try to deceive in anyway (that is not good karma), and I list to the best of my ability. I am not a jeweler, so please take that into account. If you have information about an item that I have listed that may not be correct, please by all means let me know (always willing to learn). Please see all photos for best description and dimensions, and ask any questions. Thank you for looking and stay well!