Rareness of items

Ok, now maybe I'm just being slow today or something, but as I'm still fairly new to this whole GW thing, what is the color rareness of items? So far I've figured that Gold is probably the high level stuff, but I've only seen light blue and purple stuff. Is there more colors and what is their rarity levels?

blue= not to good of mods
purple= better than blue mods
gold= best mods, some perfect (+30health 5/1 vampiric)
green= guarenteed perfect weapon however you can not add mods to it

That is actually a lie in a sense. No, blue's cannot have 15% damage mods, but you will almost never notice the 5% change. Blues are 'worse' than purples because they aren't as rare. The same goes for purples to golds.

Rarity, meaning common-ness of dropping, whites drop more than blues, which drop more than purples, which drop more than golds. The rarity means how uncommon it is for that particular item to drop in the area tthat you found it. A gold sword from the ascalon area might have completely useless mods, but is still a rare drop from ascalon area.

Example: I used to farm Riverside Province quite a bit. I never found a blue, white, or purple max damage weapon. I did however find a few max damage golds there. This was because finding a max-dmg weapon there is extremely uncommon, so it is scaled to include the only max damage you find is a gold version.

The color of the text means how uncommon it is for that area, not that it is better than another drop. Only golds can have perfect mods, but the other colors can have the same mods, just less perfect... if that helps.

Golds > Purples > Blues > Whites

Thanks, that does help a lot.

One thing to be aware of is that rareness is based upon how often a given mob will drop a given item. Each mob has a set tabel of things it can drop and these items have a base level. Each tabel has 4 differnt levels, normal (white), enhanced normal (blue), uncommon (purple) and rare (gold). A gold item from Ascalon, can easily be worse than a white item from Kryta.