"Wow that's a hell of a lot more than I was expecting, does this guy have a thing against the bank or something?" Within the storage ring there were multiple coin purses all full to the brim, not a copper in sight it, all gold and silver. There was enough here to pay for Nanna and Loki's operation and then some, easily a dozen gold.
This was a pleasant surprise and one that he'd like to keep secret from a certain money succubus. What Frost didn't realise was that Shadow was wanted throughout Northrend so he couldn't easily access the same facilities that a regular citizen could, i.e., the bank. He didn't like anyone else storing his money not even his boss Adam nor did he believe in hiding it in a secure location, where else would it be safer if not on his very person. Therefore, all of Shadow's wealth was held in his storage ring thus granting Frost a very generous boon.