Tsukineko Walnut Crystals 2 oz. Bottle. Just like walnut ink but in dry crystal form so you choose the shade you want by how much water you mix in. Mix 1 teaspoon of crystals with 1/2 cup of hot water for standard 2.5% solution or add more or less water for the shade you want. Contains 2 ounces of crystals, archival safe and acid free. Conforms to ASTM D4236