Firstly, you must ensure that you are maintaining proper records of all your transactions. Secondly, always keep in mind that these assets are unregulated in India and therefore there is high potential risk in owning or trading in them. However, you must pay taxes if you have earned an income. Seek the help of an expert who can guide you through. If you are a miner, you may have created a self generated asset. Miners also spend a lot of time and money to build these assets and therefore taxation may be a completely different ballgame in their case.