A white weapon is just a normal, run of the mill skeleton of an item, a blue one is the same, only it is unidentified and, upon identification, may have mods (not always). Purple items are also unidentified and are more likely to have more mods, i.e. it may be a sword with a pommel, a hilt, and another mod such as reduces poisoned duration, or +12% damage while health is below 50%. Gold items are called rares. They are the most likely to have alot of mods. Golds will almost always have 3 mods on them if they are weapons, or multiple mods on them if they are offhands, this may lead one to believe that gold items are the only way to get good mods. Wrong. You could find the coolest and most desired sword in the game, have it be purple and be like "shoot... no good." but when you identify it you may find it has 1 or more max mods on it. So they are always worth picking up and they are always worth Identifying. Hope this helped
