Pigments of Tokuno (Lesser, Earthen)
The Pigments of Tokuno are used to dye magical items (such as weapons and armor). This particular colour set was obtained during the second Treasures of Tokuno event as Minor Tokuno Artifacts (as were the metallic colours, albeit as Major Artifacts). There were 30 different shades, each of which had but a single use.
Note that dyes with no charges remaining disappear and cannot be turned in.
Whenever the events are active, the Minor Artifacts can be obtained by slaying creatures around the Tokuno Islands (with the exception of Cranes). The more creatures killed, the more likely an artifact would appear in your pack upon defeating the next foe.
If you have 10 such Minor Tokuno Artifacts, they can be "returned" to Ihara Soko the Imperial Minister of Trade in exchange for a Major Tokuno Artifact (even if they have been damaged through use).