In India silver rings (or rings in any other metal) are worn on all fingers, including the thumbs. The innumerable forms of metal rings can be broadly divided into those with or without a bezel (the part of the ring meant to hold a decorated device, seal or stone). Rings set with personal seals are less common today than formerly, but rings set with stones are ubiquitous. The particular stone may be chosen for reasons other than mere attractiveness. According to Hindu astrology, each of the nine planets in the Hindu universe is represented by a specific stone. Every Indian knows the planet dominant at the time of his or her birth, as it is believed to exert a strong influence on that person"s life. By wearing the stone associated with the planet, its effect can be enhanced or mitigated, according to whether the planet is malign or benign.