655. Dyeing

Shabbos 9:13

One would be liable for dyeing a thread four handbreadths long or fabric from which a thread this long could be spun. One is only liable if he uses a dye that will be permanent. If the color will not be permanent, such as using red clay to color iron or brass, one would not be liable. This is because the coloring can be removed right away. A person is never liable for performing an activity on Shabbos if it produces no permanent effect.

Shabbos 9:14

Mixing a dye renders one liable as a subordinate labor of dyeing. Therefore, if a person mixed gallnut juice with vitriol to create a black solution, or if he mixed blue plant matter with saffron to create a green solution, he would be liable. The minimum volume for which one would be liable is enough to dye a thread four handbreadths long.