Leather

Treatment of attached metal fittings

The metals most commonly used with leather are iron and copper alloys. The fats present in leather accelerate the corrosion of these metals.

A turquoise-blue, waxy material which forms on copper fittings is usually the most visible sign of corrosion.

Due to the intimate contact between the metals and the leather, immersion in chemical baths is usually not an option for the removal of disfiguring corrosion products.

In some circumstances, treatment chemicals may be applied using bentonite paste.

Most of the copper corrosion products can be removed easily using a soft, wooden spatula. Residues can then be removed using cotton buds soaked in leather emulsion cleaner.

To prevent further corrosion, coat the fittings with microcrystalline or Renaissance wax. A corrosion inhibitor, benzotriazole—5%—may be added to the wax if additional protection is needed.

Iron fittings are best treated using sanding or brushing methods to remove surface rust. Applying microcrystalline wax to the cleaned surfaces protects against further corrosion.

Copper corrosion products on studs of a straitjacket. Photograph courtesy of the Western Australian Museum

Studs after cleaning and coating with Renaissance wax. Photograph courtesy of the Western Australian Museum