Leather dyeing usually involves the use of spirit- or alcohol-based dyes where alcohol quickly gets absorbed into moistened leather, carrying the pigment deep into the surface. “Hi-liters” and “Antiquing” stains can be used to add more definition to patterns. These have pigments that will break away from the higher points of a tooled piece and so pooling in the background areas give nice contrasts. Leaving parts unstained also provides a type of contrast.
Alternatives to spirit stains might include a number of options. Shoe polish can be used to dye and preserve leather. Oils such as neatsfoot or linseed can be applied to preserve leather but darkens them. A wax paste more often than not serves as the final coat.
Sweat and grime will also stain and ‘antique’ leather over time. Gun holsters, saddlebags, wallets and canteens used by cowboys and buckaroos were rarely colored in the Old West. The red, brown, and black tones develop naturally through handling and as the oiled leathers absorb the rays of the desert sun.
Due to changing environmental laws, alcohol-based dyes are soon to be unavailable. There are currently water-based alternatives available, although they tend not to work as well.
Source:Wikipedia
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