Which haircolour is ideal for covering unpigmented hair?

The correct answer to this question is permanent. This hair color contains ammonia, and this is used to open the cuticle layer of hair. The ammonia is mixed with an oxidizing agent or a developer, which makes the color permanent.

When the cuticle layers are opened, the oxidizing agent and colorants join together to work the cortex. The higher the volume of the oxidizing agent, the higher the lift of the pigment in one's natural hair will be. Dying someone's hair permanent doesn't take that long at all. It can range from 30 to 45 minutes, but if a person wishes for their color to be darker, it can last longer.