Over the years, Omega made a few iterations of this model, either with a steel or 14K gold-plated case. Yours is probably 1973 MD 511.0458 with calibre 485 (could also be a later model with calibre 1070) Case : rectangular (20 X 28 mm) – 14K yellow goldplated (20 mic.) with stainless steel back. For
Hi Bill, nice presentation. Some nitpicking about the Marine Chronometer f2.4MHz: The prototype was actually certified as such by the Neuchatel Observatory after 63 days of testing. Its average daily drift was less than 2/1000 second per day. or 0.73 second per year. (Marco Richon) The movement phys