Honing allows you to change the attribute values of an item without changing the attribute type.
In order to Hone an item, you will need to speak with NPC "Casey" in the Market District of Hakain's Crossing while in possession of a Honing Stone.
Select the "Honing" option when speaking with NPC "Casey" to open the Hone window. Place the Armor or Weapon you wish to refine into the Target slot and the appropriate Honing Stone into the Material slot.
A "question mark" icon is displayed near the Target that lists all possible Attributes and their values that can be placed on an item. Place your mouse cursor over the "question mark" to view these Attributes.
You can also elect to "lock" a specific Attribute if you do not wish it to have its bonus change during the Refining process. Enabling a "lock" will incur an Ellun Cost that is displayed below the Material.
Upon clicking "Hone" your item will display two sets of values; the attributes before and after Honing. You will have the option to select which set of values you would like to keep for your item.