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people rarely held on to money in the form of cash for any length of time, for the most part due to lack of access to banks and/or the high cost of maintaining an account proportionate to their incomes. Cash was rapidly converted to goods based on priorities and these 'goods' acted as insurance (silver), savings (buying building materials on a piecemeal basis as cashflow allowed until the house could be built), a cushion aka insurance (selling a pig for an emergency or eaten for food) and finally investment (milk bearing cow, young piglets to rear to maturity, etc).