Pure aniline leather is a high-quality cowhide that has been dyed in aniline. Since no pigmentation is used, the natural characteristics of the hide, such as scars and scratches, show through. Natural color variations are apparent. This type of leather is prone to fading and stains.
Protected aniline leather is also a high-quality cowhide dyed in aniline, but added pigmentation creates a more consistent color. Due to the added color, the natural characteristics of the hide are less noticeable. This type of leather is resistant to fading, wear and stains.
Semi-aniline leather is dyed with a small amount of pigmentation to provide some consistency of color while still retaining some of the natural characteristics of the original hide. This type of leather is still prone to fading, but has greater stain resistance than pure aniline.