Wearingeul inks are suitable for writing and drawing with fountain pens, dip pens, glass pens and other various ink pens. These inks have great shading, sheening effect, flow and visibility. Both beginners and experts can use Wearingeul inks without difficulties.  The Color of Literature project expresses the stories and impressions of literature works with colors. Wearingeul fountain pen ink colors within this series are inspired by the moods of the literary works.  Inspired by "The Sign of Four," this ink features four distinct colors coexisting in a single bottle. The base color is purple, overlaid with a green sheen, while blue glitter and gold glitter each maintain their brilliance and distinct presence.