I always try to buy interesting IWC pocket watches that have Niello cases (which sometimes are called Tula, although that's not really correct). My latest addition is the Niello watch shown on the right. Niello is an inlay used in decorating in black on silver.
There's some discussion about these cases and the process in the archives. Briefly, the process involves engraving a design into a metal plate, and then filling the indented portions with a powdered black matt alloy made of metallic sulphides (sulphur with silver, copper, and lead), together with a flux. The piece then is heated until the alloy has melted and becomes fused in the grooves and depressions of the design. The metal, when cooled, finally is scraped and polished until the Niello is removed except in the contrasting design.
Niello decoration is found is various metal jewelry items and often is called Tula-work", which technically is a misnomer. The term 'tula' strictly applies to an alloy of silver, copper, and lead that was made at Tula, in Russia, south of Moscow, and that was used in such work. But these watches often are called Tula cased.
I bought the watch on the right because of the relatively unusual Niello design. Besides, I thought it complimented my other two Niello IWCs. All three have different movements as well. From left to right:
calibre 57, 1916
calibre 73, 1929
calibre 65T, 1927
Regards,
Michael
