Certain colors of spice are more rare than others, but they mean different things to different empires and colonies (GamingSteve.com). I haven’t really figured this out yet, there seems to be a lot of different colors. The Spore Guide indicates that the star colors of different galaxies have a meaning: Blue stars have planets rich in spices; Yellow stars have planets with a good amount of spices, and Red stars have planets low on spice.
Now, what do the different ‘Wild’ icons mean when a planet is inhabited by wild animals?
Theres 5 different spice flavours
Red > Blue > Yellow > Green > Pink > Purple
The rarity of spices varies between games, and the value of spices vary between the people you sell them to.
The different icons for planets indicate the game stage level on which the dominant wildlife on that world is. They can be creature/plant, tribal, civilization, or space. Note, that you can only colonize worlds that are uninhabited or only have creature level life, as tribal and above races “own” their world. Monoliths can be placed on any world with life to speed up the evolution of those worlds to their next stage, should that be desired/necessary.
As for spices, if you scroll down a bit on http://spore.wikia.com/wiki/Spice, it provides a table of the odds of finding certain colors of spice on certain worlds. Note that only one color is available on any given world.
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