Kundalini – the dynamo of energy based in three and half times coiled form like a snake at Muladhar Chakra (base support) in triangular shape, is too golden colored compact energy force. This is called Brahma Yoni.
Kundalini the highly compressed power is like a colied spring, ready to bounce, change from its static energy to kinetic energy under the proper conditions.
When awakened it awakens the vital Chakra centers on its way and union of feminine Kundalini Shakti takes place with Shiva Shakta at Sahastranar, which every human can achieve with some efforts. Kundalini shakti is bride, widow, virgin, wife, mother and divorcee – everything. Shiva too is a groom, widower, virgin, husband, father and divorcee. As has been followed in ancient Hindu culture, the bride, wife won't go to meet her groom, husband and consummate when others are present likewise, Kundalini won't go to unite Shiva in sahastranar when others are present like your ego.
The yogi makes the furnace of his body with his sadhana (rigorous study) and if Yoga is transcendental alchemy, the fire of kundalini purifies like concatenation, the material salty aspects, sulfur like soul and mercuric spirit.