Conserving the velvet
The 17th or early 18th century silver bookbinding is made of three distinct elements, all of them original: solid oak boards, velvet, and silver alloy decoration. However, the tannin produced by oak is detrimental to silver surfaces and this had contributed to the extreme tarnishing. Attempts to counteract the tarnish had caused extensive damage to the velvet but it was impossible to repair the velvet through the elaborate shapes of the silver. So the only way to repair the binding was by removing the silver to gain access to both the velvet and the wood.
With the silver removed it was possible to clean the velvet by brushing and vacuuming. The residues of metal polish were swabbed off using damp cotton wool pads - no chemicals were used in cleaning the velvet.