page_title: Tanning (leather)
section_title: Preparation
hierarchical_section_title: Tanning (leather) / Preparation
caption_attribution_description: English: This is a rabbit pelt that has been tanned. Possibly using inoragnic (chromic) tanning agents. You can see the fur side with some loss of fur and the underside showing staining from the tanning agent.
context_page_description: Tanning is the process of treating skins and hides of animals to produce leather. A tannery is the place where the skins are processed.
  Tanning hide into leather involves a process which permanently alters the protein structure of skin, making it more durable and less susceptible to decomposition, and also possibly coloring it.
  Before tanning, the skins are dehaired, degreased, desalted and soaked in water over a period of six hours to two days. Historically this process was considered a noxious or "odoriferous trade" and relegated to the outskirts of town.
  Traditionally, tanning used tannin, an acidic chemical compound from which the tanning process draws its name. The use of a chromium (III) solution was adopted by tanners during the Industrial Revolution.
context_section_description: The tanning process begins with obtaining an animal skin. When an animal skin is to be tanned, the animal is killed and skinned before the body heat leaves the tissues. This can be done by the tanner, or by obtaining a skin at a slaughterhouse, farm, or local fur trader.
  Preparing hides begins by curing them with salt. Curing is employed to prevent putrefaction of the protein substance (collagen) from bacterial growth during the time lag from procuring the hide to when it is processed. Curing removes water from the hides and skins using a difference in osmotic pressure. The moisture content of hides and skins is greatly reduced, and osmotic pressure increased, to the point that bacteria are unable to grow. In wet-salting, the hides are heavily salted, then pressed into packs for about 30 days. In brine-curing, the hides are agitated in a saltwater bath for about 16 hours. Curing can also be accomplished by preserving the hides and skins at very low temperatures.
caption: Tanned rabbit pelt. The fur has been left on, apart from small patches exposing leather.
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