All cowhides have natural markings. Some people are surprised to learn that the absence of natural markings can often mean a lesser quality leather hide. This is because lower grade cowhides are typically sanded to remove these markings, making the leather thinner. Below are pictures of some of the natural leather markings commonly found in quality aniline dyed or pigmented leather – especially with semi aniline, pull-up and hand rubbed finishes.  Pigmented leather will hide more natural markings due to the use of pigments instead of transparent aniline dyes.