Leather objects

Leather objects are likely to show evidence of the wear and tear that they were subjected to before they entered the museum environment. This will include splits, tears, scratches and holes, as well as damage resulting from the effects of perspiration, urine and accidental spillage of other undesirable liquids. This type of mechanical deterioration does not automatically cease when the object is placed in a collection, as damage caused by inappropriate handling is not unknown. 

Conservation can be considered to be the application of a treatment or a series of treatments to an object of artistic, historic or even sentimental value to prevent, halt or reverse deterioration. The more philosophical and ethical considerations of the profession have been discussed, among others, by Pye and the practical application of these considerations to leather objects by Sturge. 

A number of techniques using similar concepts were developed over the years to treat leathers that had already deteriorated. Aqueous solutions of potassium lactate were routinely applied to the surface of bookbindings and other leather objects. Unfortunately, in many cases, the deleterious effects of the liquid water solvent on acidic leathers took place before the buffer salt neutralised the acid, resulting in dark, seriously embrittled leather. In order to avoid the effects of aqueous solutions, methods were tried employing ammonia vapour. The object was placed in an enclosed chamber over an open dish of ammonium hydroxide solution. However, ammonia vapour is a strong alkali and there is a danger that even with the use of dilute solutions, leathers that were too acidic would be transformed into ones which were too alkaline. Another alternative was to use an organic base such as imidazole in a non-aqueous solvent. However, this was also liable to result in leathers that were too alkaline. 

The wearing of metal/leather objects or jewelry (wristwatch, rings, jewels) during manufacturing operations is prohibited. Nails shall be free from nail polish. 

Skin contact Leather objects that become contaminated with ethylene oxide, such as shoes, belts, and watchbands, cannot be decontaminated and should be discarded. If they continue to be worn, skin bums or allergic rashes may result. Skin bums from exposure to aqueous solutions of ethylene oxide should receive copious irrigation with normal saline followed by the application of a topical antimicrobial agent, such as silver sulfadiazine cream, and a dressing. Signs of skin damage may not appear for up to 5 hours following skin exposure. 

Organic Materials. Museums contain large numbers of objects made out of components from plants or animals, including wood, eg, furniture, carvings fibers eg, textiles (qv), paper (qv) fmits, skin, eg, leather (qv), parchment bone ivory etc. Several of these materials have properties related to their preservation. 

Leather is the material made from animal skin by the process of tanning, which entails chemically altering the composition of the skin so as to make it durable and resistant to decay. Leather is therefore not a protein but a protein derivative. Although the tanning process alters the composition of skin, leather retains the fibrous structure and utilitarian functionality that make skin suitable for multifarious applications. Shelter, clothing, and decorative objects made from leather are, unlike skin or hide, stable to physical, chemical, and biological decay under dry or wet conditions (O Flaherty et al. 1965 ... 

Stambolov, T. (1969), Manufacture, Deterioration and Preservation of Leather A Literature Survey, ICOM Plenary Meeting, Central Research Laboratory for Objects of Art and Science, Amsterdam. 

An armillary sphere consists of a series of bronze or brass rings, most of which can be moved, all set in an outer horizontal ring, which is fixed atop a pedestal. We use it to calculate the positions of stars and planets at various times of the year. The horizontal ring, which is called the Horizon Ring, unsurprisingly, is wider than the others, like a circular table with a very large round hole cut in it. It is possible to set small objects on it, or balance larger ones, and what I had found on it was a book bound in brown leather. 

Sally runs her fingers lingeringly on the soft leather of her seat. Maybe we could learn to see 3-D objects if we were gazing delta on to our world. But how can we ever visualize 4-D objects ... 

Measurement of pH is a potentiometric technique frequently used for measuring the degree of the deterioration of materials that are subjected to natural aging. The determination of pH levels is commonly carried out on ethnographic objects manufactured with parchment or leather, and it is especially relevant in altered paper due to the formation of acidic compounds from the decomposition of the woodpulps and other raw materials, which can induce the hydrolysis of the cellulose and then decrease the resistance and mechanical properties of the document [29]. 

It is employed by the natives of North-wcstom India for precipitating their indigo, and in tanning. English tanners, however, object to its use on account of the disagreeable color it communicates to the leather. 

When a variety of found objects such as buttons, cloth, and leather, which supply actual textures, are combined with painted or drawn textural effects on a two-dimensional ground, a collage is created. 

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