With the Material Transmutation system you can convert Equipment, Runes, Materials, and Gems that are of no use to you into other stuff. The items obtained can be Equipment or Runes, but you cannot choose the exact item you will get, it is ultimately a matter of luck.
How to use Material Transmutation
Access the Material Transmutation window from the Item section of the menu and select what type of item you want to get with the material transmutation: Equipment or Rune.
The quality of the item you will receive as a result of transmutation depends on the total points of the materials you sacrifice. Every time you add an item to the Material Transmutation window points will be added, you have to add 2501 points to raise each Material Transmutation Tier. The higher the tier, the better the possible rewards.
If you do not reach the desired Tier with the items you have available, you can convert them into points with the “Convert Points” button and save them for future use.
The rewards are random but you can limit them to a certain type of item by paying a higher cost for the transmutation process. At the bottom of the Material Transmutation window you will see the options, select the one you want, and you will see the cost that varies according to the Tier.