Not sure if the perma-tan (or sometimes a sunburn) of my swim team days ever became red ochre, but … 
Traditional nylon Speedos (pre-Lycra) didn’t stretch, so they’d cover you exactly the same every time you wore one.  That meant creating a razor sharp speedo tanline.  Mine was pronounced enough that it not only stayed around all winter, but is still vaguely visible decades later. 
		
	
		
		
		
		
		
	
		
		
	
	
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