Ruby signifies passion and unbridled, unrestrained love, making a pair of ruby earrings a perfect Valentine's day gift. A pair of black onyx earrings are an affordable and elegant gift. Always appropriate and always in style, black onyx should be in every jewelry box. Durable and affordable, a pair of blue topaz earrings are an excellent gift for a woman with blue eyes, or anyone who enjoys the beautiful color of blue topaz.