The 1960s
The decade the dial emptied out, and the one I have bought most heavily in.
The decade the dial emptied out. From the early 1960s more than 80% of watches show no numeral at all — applied markers had already taken over in the 1950s, and here they simplified into plain batons. The date window crossed over mid-decade from minority taste to default: IWC made three times as many date as no-date automatic movements between 1964 and 1976. Sizes cluster hard at 34, 35 and 36mm, with 40mm for the tool watches and effectively nothing between 37 and 39mm, while dress watches drift the other way, down to 32 or 33mm by the end of the decade.
This is where I have bought most heavily, and where I would send a first-time buyer. Chronometer certification was a volume business by then rather than a boast — Omega alone certified over half a million movements in the preceding decade — which means a good 1960s watch is a well-made ordinary thing rather than a rarity, and the parts and the knowledge to service one still exist. Watch the lume: radium was banned in 1968 and tritium replaced it, so both turn up in this decade. What matters is that the hands and the markers aged together.