In Ether 6:2 we find that,
after the Lord had prepared the stones which the brother of Jared had carried up into the mount, the brother of Jared came down out of the mount, and he did put forth the stones into the vessels which were prepared, one in each end thereof; and behold they did give light unto the vessels.
According to a F.A.R.M.S. Update, some critics have completely dismissed the Book of Mormon because they could not believe that a light source such as the brother of Jared's stones was physically feasible. For example, some have said, "the story of Ether's stone candles overtaxes the marvelous," while others have said "the words 'patently ridiculous' seem too kind."
However, Sandia National Laboratories in New Mexico has recently developed radioluminescent lights that invite some interesting comparisons with the Jaredite stones. The radioluminescent lights are made from a highly porous silica matrix --"aerogel" -- in which a phosphor such as zinc sulfide is dispersed. The radioactive source of the lights is tritium gas, which when incorporated in the aerogel, actually becomes chemically bonded to the aerogel matrix. The radioactivity of tritium results in beta particles (electrons) striking the phosphor particles and causing them to emit light while not escaping the matrix. Their life expectancy is about 20 years and their light is described as being "bright" and very "intense." Even the possibility that the Jaredite stones were created according to similar physical laws should be enough to quiet the critics. [Based on research by Nicholas Read, Jae R. Ballif, John W. Welch, Bill Evenson, Kathleen Reynolds, and Matt Roper, "New Light on the Shining Stones of the Jaredites," in F.A.R.M.S. Update Number 83, July 1992]