This is a 1960s International Watch Company automatic with a Japanese made platinum case. In the 1960s Isomura, who were the Japanese distributor for IWC watches, produced a small number of platinum cases for the Japanese domestic market. These cases were made in Japan in order to avoid the prohibitively high tariffs on importing platinum cases from Switzerland. Platinum watch cases are extremely uncommon, especially for a man's watch. I understand that this is partly due to the inherent difficulties of working with the metal, but also I suspect because there is simply much less platinum refined compared to gold. The advantages of platinum for a watch case are that it is hard as a metal and resistant to scratching and so forth. The case of this watch shows the original brushed finish and the overall is in excellent condition. IWC have a long history of horological excellence - they were founded in 1868 and have always aimed for the highest quality in their products. In the 1950s they developed and refined their first automatic movement - the calibre 85xx series. This movement is well respected, the great horological author Donald De Carle describes it in his book "Complicated Watches" as "a simple and ingenious system, well constructed and beautifully finished". Elements of the automatic winding system are still found in contemporary IWC watches. The serial number of the movement dates it to around 1961, the movement is the calibre 8531, which features the addition of a date mechanism to the base 853 movement. This was IWC's flagship movement at the time and it is superbly constructed. The balance spring has a Breguet overcoil to enhance time keeping across different positions, along with Reed-type regulator, which allows for very, very precise adjustment of the time keeping.The watch has been fully serviced and regulated, while the case has been cleaned by not re-polished. The watch is fitted with a nos vintage strap, which complements the watch wonderfully. Case diameter (excluding winding crown): 35mmCase material: stainless steelstrap width: 18mmtime keeping: grade A+
