whether selling my wife's jewelery and investing on bitcoins makes sense?
Is it reasonable to invest in gold rather than bitcoin?
If it's reasonable to do so should be based on your own view and not ours. You are dealing with a plan where there are lots of "what if". No one knows if that plan of yours will be effective in the long run. Both choices considerably make sense but that would not end there as on the way, you need to take action in order to fully utilize what you did.
Diversification or doing all-in, it's your call. Good luck.