The main gemstone for the Sun is a Ruby. It should be a minimum of two carats in size. It should be set in gold of fourteen carats or more and worn on the ring finger of the right hand. It should be a good quality, without flaws and transparent.
As a substitute, garnet can be used, but it should be of at least three carats in size in case of ring and preferably five carats when a large garnet pendent or strand of garnet which can be worn around the neck.
These gems should be put on first on a Sunday, preferably at the rising of the Sun, particularly when the Sun is strong, as when in its own sign or exalted (also good is in Sagittarius).