From MewsiEPTO Wiki - Unofficial Eternal Paula Trickster Online Wiki
Basic Info
Refinement increases a particular stat for each set of gear (You can see which stat by Rclicking the equip in your Inventory and looking for the "Refine" box)
You need ores from the mines to achieve this
You can use Anvils (up to level 11) and Refine Fortune to increase your refine odds
Physical equipment and Magic equipment use different ores
Weapons use more stones compared to Shields and Hats
TIP: The mines at Snow, Techi, and Tapasco all have Harkons as their final quest reward for Blacksmith Marx! Use this for guardian and 3rd job advancement!
You can also find the same information listed on this guide here