The stone weighs about 10-12 Kilos is floating in Rama kund in the temple tank. This is demonstrated by HH.Bhakti Vikasa Swami Maharaj. It's not a big wonder that a simple stone is made to float by the Supreme Lord Sri Ramachandra. The Lord makes planets containing oceans and mountains float in space what to speak of water.
Is it God or is there a scientific rationale?