Warded Jars and Labels is a research option in the Alchemy tab that is unlocked upon discovering Essentia Distillation. Warded Jars and Labels details what Warded Jars and Labels are, and how to create and use them. Their main use is in storing Essentia in large quantities for long periods of time, but they have some crafting uses as well.
Warded Jars can either be stored or placed down in the world, whether empty or storing Essentia. Each jar can hold up to 64 Essentia and stack, when with Jars of the amount and type of Essentia, up to 64. This makes storing massive amounts of Essentia relatively easy, as Jars are a safe way of storing Essentia and can be stacked. Warded Jars are created at an Arcane Workbench with 7 glass panes of any color and a wooden slab of any color along with 5 Aqua Vis. They have some uses in Infusion and crafting, but their main purpose is as a receptacle for Vis, and a place to efficiently store it without fear of leakage or decay.
Labels can be placed on Warded Jars containing Essentia, or marked using a Phial of Essentia, which will not consume the Phial or the Essentia in it, to limit that Jar to receiving only that type of Essentia. They can also be placed on Filtered Essentia Tubes to limit the flow of Essentia to only the marked aspect. They can be created at any crafting station using 4 paper, a slime ball, and an ink sack. Both of the latter can be created Alchemically after researching Alchemical Duplication. Labels can stack in up to stacks of 64, but only if blank or assigned to the same type aspect.