The article describes the restoration of a 16th century organ in Florence (Italy). The gilding of the ornamental facade of the organ in the church of Santa Trinità was coated with a layer of purpurin varnish. The first phase of the restoration was thus to remove the purpurin and the underlying red varnish with a solvent gel and a scalpel for the move teracious parts. The original coating was then fixed with injections of alcohol and rabbit glue. The missing carvings were reconstructed. Reintegrated parts were plastered and the gold replaced and burnished with agate. A final protective coat of varnish was given.