How affix-like modifiers are applied to items ?

[Morderoc]

Hello there,

I try to understand how modifiers are applied to items. Say the base item is "Rubber Sword", this same item can appear in the loot as "Fine Rubber Sword", and have more damage, or the item "Pink T-shirt" would have a "Ragged Pinked T-shirt" version, etc.

 

Are these random modifiers ? How are they created in-game ? As far as I understand, items have an ID (that you can use to spawn them in your inventory) but nowhere is to appear a modifier ID.

It bother me since a few days, when I found a "Heavy Heavy Something" in my loot window at the end of a battle.