Stevekir

I have no problem with tuning the RC circuit to the frequency of the crystal. But how is it that the crystal used vibrates at the fixed speed of 32,768 vibrstions/sec. Is this number decided by nature? If so it is a remarkable coincidence that Providence has provided a number capable of being divided by 2 15 times (or any other suitable number to replace the 15) to give a pulse of once per second. There is an infinite range of numbers in the world (such as 32,769 to (2 x 32,768-1)) that would not give this exact result and if Nature had "chosen" one of these, a quartz crystal could not be used. Could the answer be that by manufacturing the crystals (by the million), they could be tested for the few that had the correct property? A time-consuming task. What's the answer to this conundrum please? Thanks.