Originally Posted by azflycaster
The skin is an alloy with a thin layer of pure aluminum on the surface.
Don't think you'll find "pure aluminum" outside a lab. Like most metals it needs to be alloyed to be useful.
If you're really interested in materials I suggest Carroll Smith's "Engineer to Win"
If you're interested in rivets and every other fastener it's "Screw to Win" or " "Nuts, Bolts, Fasteners and Plumbing Handbook"
I can't give enough praise to Smith for his straightforward writing and invaluable technical details. If you want to know about Cherry Q rivets and when to use them this is your reference. I guarantee the money spent on his books and time invested in reading them will reap dividends far exceeding your cost.