Offer your thoughts or opinion on the input financial query or topic using your financial background.

Is is possible to take a mortgage using Bitcoin as collateral? 
This doesn't make any sense. For the people who ask you this, suggest that they borrow the money to invest with you. They can use their bitcoins as collateral for the loan. That way, they get the same benefit and your company doesn't go out of business if the price of bitcoin drops, even temporarily, because the loan becomes unsecured. If they want to try to use a volatile asset as collateral and have to figure out how to cover when the price drops temporarily, great. But why should they put that risk on your other investors who may not be so crazy? Also, this obviously won't meet the investor's concerns anyway. Say the price of bitcoin goes up but you lose 10% of the money you borrowed. Clearly, your investors can't have an interest that worth as much as they would have if they held bitcoin since you lost 10%.