Flyingass and Alchemy,
Many thanks for being so gracious and doing all that math. God knows I am totally math handicapped, having studied only Architecture in a recent incarnation.
Found this point of interest in another forum somwhere:
"the specific heat of aluminum, by mass, is quite high - about twice that of iron and nearly 2 & a half times that of copper. However, aluminum has roughly a third of the density of iron or copper, so it's specific heat by volume is nearly the same."