Here's the quest and you can read the dialogue here~ http://xivdb.com/?quest/66971/Up-in-Arms
Quote:#18 Jalzahn
Now, I trust you are aware that aether permeates all things in our world. What you may not know, however, is that aether is found in greater concentrations in Eorzea than elsewhere.
#19 Jalzahn
When a weapon infused with a quasi-soul such as your relic is used to slay a living being in this aether-rich land, a peculiar phenomenon occurs.
#20 Jalzahn
The aether released by the fallen creature resonates with your weapon, and agglomerates into a crystal which I have dubbed “atma.†It must be noted that this occurs only on rare occasions, due to factors I have yet to identify.
#21 Jalzahn
Now, as you may have already gathered, atma is essentially the crystallized soul of a living being. And these crystals hold the key to strengthening your weapon.
#22 Jalzahn
According to my research, twelve unique pieces of atma are required, meaning they must be acquired from twelve different foes. See the deed done, adventurer, and you shall hold in your hands such power as you have never known!