One of the many questions received regularly is to date the age of a music box.
Many music boxes were cherished heirlooms from mother or grandmother, with touching stories to go with it, but often thought older than they in my experience are. Some suppliers as Mann and Otagiri were good at putting a year of production on their music boxes, but such labels were often taken off or fell off in time, thus still leaving us with a mystery.
One imperfect way of dating is to look at the origin, if that is still available. Made in Japan generally dates to the seventies or earlier, as after that the production switched to other countries. The exception to that rule is a.o. Otagiri, that well into the eighties kept music box production in Japan.
From Japan it switched to Taiwan, with the heyday being in the eighties, and also to Korea, The Philippines, Macao, Hong Kong. From the nineties the production switched almost wholly to China.
There are certainly many exceptions to the timeline sketched above. Another way to date is to look at the plastic parts used in the music mechanisms, as over time more and more plastic parts were used. The music mechanism is not always easily accessible and my advice, that i follow myself, is to rather not be able to inspect the mechanism if it would damage or devalue the music box; be careful what you do!
Up till almost the end of the seventies, both in Japan and Europe (Reuge), the first plastic
part, an axle and wheel to the governor, appeared; before that time the music mechanisms
were wholly made of metal only. This first plastic part covered the very end of the sixties
and the seventies.
Than late in the seventies and mainly in the eighties more plastic parts appeared, specially
an inner plastic tube in the cylinder with wheels and a plastic wheel in the spring chamber.
Also the governor is mostly being made of plastic at this time.
In the nineties most parts of the music mechanism are made in plastic, including the spring
house and only the bedpan, the cylinder and the comb are still made of metal.
Between the 2 methods, origin and plastic parts in mechanisms, a rough dating is possible.