Tourmaline is known as the gem of love and commitment. Buy her a pair of pink tourmaline earrings to seal the deal! The birthstone of February, amethyst makes an appropriate and affordable gift. A pair of amethyst earrings in a stud or dangly design are always popular and always in style. Ruby signifies passion and unbridled, unrestrained love, making a pair of ruby earrings a perfect Valentine's day gift.