Uses chromium sulfate and other chromium salts. More subtle and pliable than vegetable tanned. Does not discolor or lose shape in water as badly as vegetable tanned
Uses glutaraldehyde or oxazolidine. leathers tanned this way often used in cars and kid’s shoes
uses tannins and other ingredients found in vegetable matter. Must be used for leather carving or stamping. Leather treated this way tends to harden when exposed to water.