The invention discloses a method for treating an animal substrate comprising: agitating the moistened animal substrate with an aqueous treatment formulation and a solid particulate material in a sealed apparatus, wherein the aqueous treatment formulation comprises at least one colorant. There is also disclosed an animal substrate obtained by the method and finished leather goods obtained by the method.

The invention discloses a method for treating an animal substrate comprising: agitating the moistened animal substrate with a treatment formulation and a solid particulate material in a sealed apparatus wherein the treatment formulation comprises a tanning agent or a tannery process agent. The method can comprise applying the tanning agent or tannery process agent to the animal substrate wherein at least some of the agent so applied originates from the treatment formulation. There is also disclosed an animal substrate obtained by the method. The treatment formulation can be aqueous.