(This black has a bluish cast to it.) PRO MX Reactive Dyes (Procion) are easy, versatile and permanent. Use at room temperature (75 - 95 degrees F) on plant based fibers: cotton, linen, ramie, hemp, viscose rayon, bamboo, jute, paper, wood, basket reed, even silk. These dyes can also be used (with a different procedure) on protein fibers such as wool. Procion dyes are completely intermixable and have excellent wash and light fastness. Two ounces (58 grams) of dye will color 3 pounds of cotton fabric (approximately 14 yards) to a medium shade in a solid shade dye bath, or 12 T-Shirts for tie dye. Suggested auxiliaries for PRO MX Reactive Dyes: Soda Ash, Synthrapol and Urea. Note: These swatches are a representation of the actual dye. Please test colors before beginning a project requiring an exact color match. When using these dyes for Ice Dyeing, please keep in mind that you will see the components of the mix not a solid color. For Example: when using blacks, you will see the individual colors from the mixture, not a solid black.