As paint drops dry, they can look like a “fried egg” (left image, scale bar is one millimeter) or develop a more even pigment distribution (right image). A coffee spill leaves behind a dark stain ...

A coffee spill leaves behind a dark stain around the puddle’s edge when it dries. But as drops of paint dry, some look like “fried eggs,” with “yolks” of color surrounded by pristine white halos, ...