I am more inclined to experiment in Harvest Moon than to research the results of other players. I am certain there are lists of Accessories produced through the Multiplayer option in Rune Factory 2 somewhere but I always want to discover new territory myself.
Thus, a seemingly endless quest for materials to create Weapons at the Forge and Accessories at the Workbench, raising each to Level 10 before 'trading' it to see if it undergoes a strange sea-change and is transformed into a new item.
I am amazed by the sheer volume of Gold Ore required to create most of the 'superior' upgrades in Rune Factory 2. It is when the actual upgrades require 1 or even 2 pieces of Gold Ore that one becomes rather overwhelmed sometimes. After all, 2 pieces of gold for each upgrade means that you will need a total of 18 in order to upgrade a Level 1 Weapon or Accessory to Level 10. In many cases, the original item requires 4 pieces of gold as well to create...
The fact that I almost have completed the List is more of an achievement than any one who hasn't played Rune Factory 2 may not comprehend fully.
In any event, here are a few examples of Accessories that are transformed into new items when traded at Level 10. Unlike the unique Weapons created in the same fashion, these are items that CAN be created at the Workbench, but only if your character has high skill levels.