pink
Brown, of couse!
Pink .
Charlie Brown's hair is typically depicted as black in the comic strips and animated TV specials.
silver
1950
It's bark was brown and the few needles on it were green.
Bulk aluminum is usually a silver color. (Think aluminum foil.)
Somebody says these primitive forms of multicolor strobe lights came out in the l950"s and that sounds about right.They did in the late 50's and into the 60's aluminum Christmas trees were very popular.
white perhaps
Yes, aluminum does not change color when heated.
chocolate
Yes, they can be used. You may also want to look for a color wheel to go with it. When the aluminum trees came out they also had a wheel that rotated with different colors on the tree. Nothing can catch fire on these trees and they are very "modern" in their way.