Lime (calcium hydroxide)
It is possible to create a vat from indigo, lime (calcium hydroxide) and over-ripe fruit such as dates relying on the chemistry of the sugars* rather than fermentation of the fruit. But it’s easier to simply use fructose shared in
Michel Garcia’s 1-2-3 recipe. It’s very simple: One Part indigo,two parts lime and three parts fructose, plus warmth.