rough: oyster
smooth: oyster pearl

land: pure desert, warm colors
sea: pure sea, cool colors

trash: pile of junk
treasure: pile of gold, diamonds, etc.

hidden: where's waldo esque, lots to look at with text hidden
visible: blatant large text, bright, eye catching, dull background

fresh: will smith
rotten: moldy bread

robot: person with cardboard robot outfit
homeless: homeless person in cardboard box