Leather

Untanned skin products

Rawhide

Rawhide is the dried skin of an animal which has had all of the flesh removed. It is usually a very rigid, tough material. Despite its inherent toughness rawhide is in many ways the least durable of the skin products.

It is used in the manufacture of suitcases, and for hammer heads, drum coverings, thongs and lashings.

Parchment and vellum

Parchment and vellum are made by stretching the skin on a frame and drying it. The skin is treated with lime to remove fat and hair, and it is washed and scraped repeatedly.

Parchment and vellum are untanned animal skins. Occasionally, tanning solutions are applied to the surface of the parchment or vellum to improve its surface quality.

Parchment and vellum are usually light-coloured, almost opaque, and smooth. They take ink and colours well. Both were widely used as writing materials before the introduction of paper to the West. They have also been used as bookbinding materials. Translucent parchment and vellums were also produced, and sometimes used as window panes.

The terms parchment and vellum are sometimes used interchangeably. Originally vellums came from calf skins—the name vellum comes from the Latin for calf. Vellums tend to be whiter and of better quality than parchments. Modern parchments are generally thought to be inferior to earlier parchments. Many modern parchments tend to be yellowish in colour, a bit greasy and thin. These parchments are often made from split sheepskins.

Never force curled or distorted parchment to open out or to lie flat—this can cause damage. Humidification and drying under tension can restore the parchment but this should only be done by a conservator.

Semi-tanned leather

Semi-tanned leather—buckskin or buff leather—is produced when skin is stretched and an oil and fat emulsion, usually from the brain of an animal, is rubbed into it. The skin is then manipulated until it is dry, soft and flexible. Often it is smoked in the final stage of treatment.

New, semi-tanned leather is soft, suede-like, extremely flexible and durable.

In earlier times, semi-tanned leather was used for clothing, lining, pouches, gloves, saddle seats, and military uniforms and equipment. The most common modern example is chamois or wash leather.

In museums, galleries and libraries, untanned and semi-tanned skin materials must never be allowed to come into contact with water.