Re. stockmarkets - I suppose the basic meaning of 'stock' is simply one's 'holding' in something, ie one's property. Hence your holding in a company, ie your shares, can be described as 'stock'.
Likewise in a more primitive agricultural society before the advent of industrialization, your 'stock' would largely consist of your animals.
It's worth noting that the Latin word for 'money' was 'pecunia', which is undoubtedly closely connected with the word 'pecus', which is a herd of cattle.
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On a mountain range
I'm Doctor Strange