"I seem to recall that the shells were aluminum??"

The cases were indeed aluminum and are pricey collector's items nowadays. I understood they were the result of an experiment in shell technology by John Olin; but if so, I've no idea as to why he selected a 14-bore as opposed to another gauge? Supposedly only 4-5 experimental Model 59's were made for testing purposes; and if true, I'm certain there's many Winchester collector's still hoping to fill this niche.