Thanks goes to our fellow forum member "Enforcer" from our forum. More info on the guide can be found here: http://www.perfectworld.cc/Forum/Default.aspx?g=posts&t=183 !To upgrade weapons and items one needs
Upgrading gems.
Type 2 Upgrading gem required to upgrade weapon to +1
Type 1 Upgrading gem required to upgrade armor pieces to +1
How to get Upgrading GemsFirst off, find the right NPC: He usually is somewhere around the Vault NPC (Stone Collector xyz)
Basically there are 2 ways to get upgrading gems:
1.) 3 Human Celestial Stones + 3 Hell Celestial Stones + 3 Heaven Celestial Stones = 1 Upgrading Gem2.)25 Celestial Stone Fragments = 1 Upgrading GemThroughout your leveling process there will be repeatable quests at certain Quest-NPC's that you can attend to. These each reward 1 Celestial Stone Fragment.
These quests first start off at the Sentinel in Village of the Hidden Hero at lvl 6 up to lvl 10.