This is now my solution for perfectly neutral darkest brown hair with no grays and no brassiness. My hair is waist long, fine and not color treated. My hair is naturally medium/dark brown but with UV rays it becomes very red toned.
I follow the single step process of combining henna + amla and indigo + salt. I combine about 30% henna and 70% indigo. Use water to mix. Wait 4 hours. Rinse with conditioner. Shampoo after 24 hours. And it's perfect.
Begins almost black but over a few weeks becomes darkest brown to dark brown, while remaining neutral. I was very surprised that the results lasted as long as they did. 4 weeks of darkest brown then another 2 weeks of dark brown. It's been 10 weeks since my last treatment and I still see a neutralizing effect.
I've used other henna in the past and they simply do not compare. This is somewhat more involved with custom ratios and add-ins but for both price and quality, this is it. I will use Henna Sooq forever.
Thank you for creating such a great product and providing knowledge for the community.