They're often valuable for vastly different reasons â like the World War II-era coins minted from atypical metals, or double-printed pennies â but each one is easy to miss if you're not paying attention. See also: Californian Couple Finds $10 Million Worth of Gold Coins in Tin Can.
A subsistence economy is a non-monetary economy which relies on natural resources to provide for basic needs, through hunting, gathering, and subsistence agriculture.
The subsistence agriculture has given way to commercial agriculture to some extent. Dry land farming is practised in areas where the rainfall is low and irrigation facilities are inadequate. Here, emphasis is laid on conservation of moisture, and on crops like jowar, bajra and pulses, which need less water.