This Mid-Century cocktail ring stands out with its unique design featuring an 18 karat yellow gold body. The ring has .40 carats of round brilliant diamonds (SI1 clarity, H color) in the middle, surrounded by triangle-shaped black onyx stones that create a bold contrast. The oversized, navette-shaped design makes this ring noticeable, while the split band adds an interesting detail to its overall look. 

This piece combines elements from the experimental Mid-Century period with a mix of diamond and black onyx. The ring works well for anyone who likes jewelry that blends different design periods into something unique and eye-catching.