A shivling in general symbolizes the union of mind and soul. It also physically symbolizes the male and the female reproductive organs in a state of bliss. … A Shivling means the combination of ‘Shav’ or the body which Lord Shiva gives and ‘Shakti’ or the power of the soul.
Shiviling is available in different materials and one such is, the one made of mercury – liquid metal. Mercury is known as Parad (in Hindi Paaraa). What importance does it hold? It is not mere conjecture but in actuality human mind is more often than not unsteady, and Parad too has the same property. If mercury is stabilized through different processes and a parad shivalingam made out of it, it has tremendous stabilizing effect on the person sitting next to it and meditates.