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I asked for metallic Concrete with silver glitter added and metallic Goldenrod for the stripe, got something that very much looks like it is not metallic but just a flat color with glitter added, but CS denied, saying the metallic effect merely didn't turn out so well with that color. Plus Goldenrod is a lot less orange-ish and a instead a lot more yellow-ish than what I estimated it'd look like from the color picker swatch. Oh well.
What I had in mind with the colors was a play on level design for computer games, in particular Hammer / Source Engine. During development and playtesting, where visual details don't matter at all yet, level designers often use simple shapes and placeholder graphics. Iconic for Hammer are the supplied gray-orange "dev_measuregeneric" textures made specifically for design and testing.
will definitely bring the cavalry next time! 
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