EVERYTHING IS RELATIVE TO REAL LIFE
.COLOR
Skin color occurs within natural ranges
Hair color typically occurs within natural ranges. However, it is possible to have exotic hair colors. (Red, Orange, Blue)
Eye color typically occurs within natural ranges. But can also follow the hair color. Evaluated on a per eye basis. So heterochromia is a bit more common.
However WHITE (#FFFFFF) never occurs naturally. Not from aging or any other process.