Skybuilders' Ink

Skybuilders' Ink is miscellany used in the Ishgardian Restoration.

Source
Skybuilders' Ink can be crafted by alchemists as a level 20 recipe with the following materials:
 * x6
 * x1
 * x4
 * x2

Uses
Skybuilders' Ink is exchanged for in custom deliveries to Potkin in The Firmament.