Shivling is worshipped in two common forms – Chala (Moveable) Lingam and Achala (Non Moveable or fixed lingam). The Chala lingam may be kept at one’s own home for worship. Chala Lingams are often made of gemstones, quartz, brass, parad or other metals. Achala Lingams and installed at temples and are un-movable once they are installed. These are usually made of stones. There are rigid rules for achala lingams which must be followed. Achala Lingam must be offered prayers at fixed times and without