Marbleized maroon trim pieces - unused 3 bullnose (top) trim.
Length: 6 3/8"
Height: 1 3/4"
Unmarked, manufacturer most likely Miraplas.
Web info: https://archive.org/details/HowToDecorateForLastingBeauty-WithMiraplasStyronWallTile/page/n15/mode/2up
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