Yeah, it was
not hard to rub off and came off all over.
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For hand inserts or other instances where Brent would put his hand on a console and leave a giant gold handprint, they would spray over the make-up with hair spray to fix it.
It was white makeup with a gold powder dusted over it. As with many of his make-ups, it was probably a custom mix by Michael Westmore, though I have seen people at conventions with very good approximations of it.