Selling used gold as new after processing it

Q: I bought some used gold, then I refined it in a way to make it look like new before selling it at the price of new gold. It should be mentioned here that I did not inform the buyer about this. Is this sale permissible?

A: If the case is as you have mentioned, it is impermissible, for it is a form of fraud. May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.