The Yantra employs signs and writings to remove a planet's malicious
effects and increase its beneficial results. Thus, Vedic Yantras are the
graphic representations of Mantras. Yantras can be drawn, engraved or
painted on a variety of substances like the eight tantrik surfaces -
gold, silver, copper, crystal, birch, bone, hide (which can include any
type of paper), and Vishnu stone (Shaligrama). The Yantras should be
beheld daily in the morning and one should lit incense stick or lamp
before it every morning. Yantras are equipped for different purposes and
every purpose has to be acquired through specific type of Yantras.