Natural blackish henna for hair is a mixture of henna, indigo powder (Indigo era tentoria) and organic herb. Its 100% natural, and hence there are no side effects. It covers your grey hair naturally. It also helps in making your hair healthier. Natural blackish henna for hair is a mixture of henna, indigo powder (Indigo era tentoria) and organic herb. Its 100% natural, and hence there are no side effects. It covers your grey hair naturally. It also helps in making your hair healthier. BENEFITS: It covers almost all grey from your hair and gives you a Natural blackish brown colour. It makes your hair shiny and glossy. It is 100% natural, thus has no side effect. Hair gets good protein, which helps in preventing hair from getting dry. HOW TO USE IT? Take an aluminum bowl and mix a pack of 500gm with one cup of water. Mix well with a stirrer. Make a thick paste and then add buttermilk to it. Add 2 tbsp. of black tea water. Then apply it on your hair for 2 hours and wash it thoroughly.