Katam by Phitofilos is a pure powder that is obtained from the leaves of the Buxus Dioica tree. The dark green powder results in a nearly black colour result with violet undertones (unlike indigo that has blue undertones). Due to it being a purely natural product, Katam requires a certain amount of time to oxidate. Therefore, the colour result may only be visible on dry hair after a few hours. 
Classic application: 
The application/reaction time on brown or dark brown hair corresponds to 40 - 120 minutes. 
Light brown hair, with or without few grey hair, will be given a dark, cool shade. 
Grey hair: it is advised to pretreat grey hair with a basic colouration using Henna Red No. 2 or No. 3 (10 - 40 minutes). Apply the Katam paste immediately after rinsing the henna pretreatment and leave on for 40 - 120 minutes. 
Application: 
Depending on the length and thickness of the hair, mix the required amount of powder with hot water or black tea until a creamy paste is formed. 
A pinch of baking soda can also be added to the water being used for mixing. 
Leave the mixture to rest for 1 - 2 hours while stirring occasionally. 
Apply the paste to clean, towel-dried hair. 
Wrap the hair in clingfilm or aluminium foil and leave on for 40 - 120 minutes, depending on your desired colour outcome. 
Thoroughly rinse the hair and dry as usual.