Abstract: An apparatus is provided which can easily, efficiently, reliably and thoroughly blend or mix hair colorant chemicals while minimizing stylist exposure to noxious fumes. The apparatus may include a mixing bowl molded from a polymeric material, an interlocking lid molded from the same or similar polymer, a specially designed top lid, a motorized handle, and a stiffing paddle or whisk having a rotatable shaft which passes through a sealing means removably affixed to the specially designed top lid and thence engaging a driving end of the motorized handle. The top lid incorporates interlocking means at its outer edge such that it can be easily twist-locked into intimate contact with the bowl which is provided with mating lock surfaces. When engaged, mating surfaces of the top lid and bowl form a seal which prevents or minimizes escape of mixture ingredients and odors from the enclosed volume defined by and between the lid and the bowl.