As loans go, the Federal Reserve's $29bn to facilitate JPMorgan Chase's acquisition of Bear Stearns is certainly unusual. Market participants perusing the Federal Reserve Bank of New York's description of the deal will have found few answers to the questions uppermost in their minds.

To kick off with a few, we do not know the nature of the assets that serve as collateral for the loan. JPMorgan had, on its first iteration of the Bear acquisition, suggested that some of the gross exposure it was taking on and then offsetting via a non-recourse facility - which one assumes was the Fed loan - was roughly split between commercial real estate and residential (mainly prime and Alt-A) mortgages.