It is hard to find a better example of how silver protects purchasing power over long periods than to look at the story of the Australian 1966 “round” 50 cent piece.
Soon after the coins release, the price of silver started rising and it was no longer feasible for the government to make the coins from silver. No 50 cent coins were struck in 1967 and 1968, and the next 50 cent coin was issued in 1969 with the same design, but instead of being round it was a copper-nickel dodecagonal (12 sided) coin.
Back in the late 1960’s 50 cents was a good sum of money. In both 1966 and 1969, 50 cents could buy you a decent lunch. Fast forward to today and let’s see how the coins have held up.
An average circulated “round 50 cent piece sells for its silver value of between $11.50 and $12.50 which is still good enough to buy a decent lunch with maybe a little change. The 1969 copper-nickel 50 cent piece in average circulated condition is worth its face value only. It is hard to buy anything for 50 cents in Australia these days and you certainly can not get a lunch at all.
1966 “round” 50 Cents Nominal Specifications