Every planet is associated with a gem and a sub gem which is believed to receive beneficial influence from the planet of that gem.
The principle behind the remedies through gems is very simple that when a planet is positioned in a weak place and if it is also beneficial and auspicious in the natal chart of a person then such a planet should be made strong by the gems of that particular planet. As mentioned earlier each planet is related to a particular gemstone. In the Ayurvedic field of science the powder extract or the bhashma which is got by the crushing of the gems is used in treating various diseases because of it high medicinal values and features.