Adiamond solitairerefers to any piece ofjewelry with a singlediamond.Diamond solitaires can be a ring, necklace, earring or even men'sjewelry. They have come to mark some of the most significant occasions in one's life, like sweet-sixteen, anniversaries, and the most notable, anengagementproposal. symbol of their dedication, love, and commitment to each other. It is a symbol of the beautiful journey that two people embark upon when they decide to spend their lives together. .