Large silver coin = 100 rares, about the size of a 100 yen coin.
Gold coin = 1,000 rares, about the size of a 1 yen coin.
Large gold coin = 10,000 rares (10 gold coins), about the size of a 100 yen coin.
Shiro gold coins = 100,000 rares (100 gold coins), about the size of a 100 yen coin.
Gold and silver coins are alloys with smaller amounts of gold and silver.
Since copper coins are generally not in circulation, retail prices are usually in units of 10 rares.
When merchants deal in gross units, they sometimes give a unit price of one rare unit.
Large gold coins cannot be used at stalls, and white gold coins can only be accepted at very large stores.
The unit price of a loaf of bread is about 10 yen per rare, but this is just a rough estimate because prices vary greatly from region to region and labor costs cannot be compared.
For example, if you use apples (or other fruits), the price would be about 1 yen per rare.
A family of four can get by with five gold coins for a month.