If these items were found in China, then historians would most likely attribute them to the Han dynasty or the like. Why? Well, because in China they knew the wheel, so the use of the first primitive mechanisms was “allowed”. An example is the mold for a bronze ratchet wheel (China, 206 BC – 220 AD)
But the whole problem is that such products were found in South America in Peru and attributed to the so-called Andean civilizations with an official date from 300 BC. / 300 AD, which means that such products in this region simply cannot be gears, but they may well be … a mace – and they became it (according to the museum catalog).
However, explain the difference between the gears of the same Middle Ages or the same Antikythera mechanism of the ancient Greeks
one of the parts of the antikythera mechanism
and the “clubs” of the Indians … not just
Moreover, in the “clubs” of the Indians, in addition to the teeth themselves, there are also such pronounced gear details as:
grooves and spokes to reduce the weight of the gear + for damping a significant vibration shock of the drive gear (what a shame for a mace ?!)
in addition, on one such ancient Peruvian “mace” one can see a corrugated profile in the form of a “mesh” (a clear imitation or dummy from some vanished original)! Maybe in the original they were blind grooves? ..
And even elements of an involute profile …
Why these are just dummies, I have my own explanation, more details can be found at the link (https://zen.yandex.ru/media/mexahizm/obnarujeny-indeiskie-busy-iz-detalei-kolumbiiskogo-samoletika-detal-opoznana-5ee38be296181e71f8c8bed7).
Similar elements (rim, hub, grooves, spokes, etc.) are present on modern gears.
For example, gears for a radio-controlled helicopter …
or for a bike
Yes, in almost any …
And since there are already several dozen such artifacts found in only one museum – Museum of Anthropology, Vancouver, Canada
some exhibits code: Sf517, Sf519, Sf509, Sf505, Sf520, 2990/782 … Composition: copper + gold. Dimensions: 1.5-2 cm x 8-10 cm.
then we can assume that in fact there should be even more of them (see another topic). And as I said earlier, all these gears (let’s call things by their proper names) are just copies of some original details of some old lost mechanism – the mechanism of that extinct civilization, which the Indians themselves called “gods” …
Perhaps it was a gearbox, the condition for the functioning of which was the lightest possible form of the entire unit (see topic), or other conditions.
What was this unit? .. Write your comments.
ps And yes, the version of historians also has every right to exist. Moreover, it may well be working. Modern gears can be used as a great mace too!