A natural leather chamois (pronounced “shammy”) is a soft, absorbent and durable drying cloth made from sheepskin leather tanned with marine oils. Chamois are preferred for most high-end applications because of their ability to protect the surface being dried from scratching, marring and swirl marks. Unlike other drying towels, a chamois’ not only has a large amount of nap, which serves to pull dirt and grit away from the surface and into the fiber structure of the towel, but will release the dirt and grit more effectively when rinsed; so the towel does not become abrasive over time.
When choosing a chamois, the best and most efficient weight is a medium one. A light weight chamois will not absorb as much water and will tend to have less tensile strength. A heavy chamois is more difficult for the user to squeeze the water out. A medium weight chamois is the best combination of water absorption, strength, and ease of use.
Although the technical definition may differ slightly by country (see below), the internationally accepted definition of a genuine leather chamois is leather prepared from sheepskin or lambskin, where the grain has been removed and tanned with fish oil. Unlike synthetics or other petroleum-based drying products, a genuine leather chamois is a natural, and reoccurring, byproduct of sheep ranching and food production.
In the United States the definition of a chamois is established by Federal Specification KK-C-300C and further outlined in the industry adopted US Federal Standard CS99-1970. That definition is further refined by Advisory opinion #1, Section 5, Federal Trade Commission Act. ”The necessity for splitting sheepskin is to remove the impervious grain layer so as to make the underside more receptive to tanning. Since the two layers do no stretch uniformly and will eventually rip and crumble. In any event, irrespective of the relative merits of the many processes which may be employed to produce the leather, the fact remains that the grain layer must be separated from the sheepskin flesher in order that an acceptable chamois will result.”
While The British Standard 6715: 1991 defines a chamois as "Leather made from the flesh split of sheepskin or lambskin, or from sheepskin or lambskin from which the grain (the top split) has been removed by frizing, and tanned by processes involving oxidation of marine oils in the skin."