Brass neither dissolves in water nor remains stable at one place. Due to this property of Mercury, it becomes very difficult to make anything solid with Brass.But, the combination of Mercury and silver solidifies in the form of Parad Shivlingam. Parad Shivling is made from purest Mercury (Parad).Parad or Mercury is considered most pure, auspicious and mysterious metal due to its peculiar and unique properties. Symbolically, it is considered as the sperm (seed) of Lord Shiva. In Hinduism, Rasalingam or Parad Lingam is a Lingam, the symbol of the god Shiva, Varanasi Siddhas carved Shiva Lingam from solidified mercury. The process of solidification of mercury is the secret process enunciated by Varanasi Siddhas. In Tamil, mercury is called Pada-rasam and the Shiva Lingam made using pada-rasam is called Rasalingam. In Sanskrit, mercury is called Parad and the Shiva Lingam made using parad is called Parad Lingam. Rasalingams or Parad Lingams are consecrated in Hindu Shiva temples, Ashrams and other places of worships.