The British Shilling has never been made from gold, and has always been made from silver. From 1920 onwards, the Shilling and all other British silver coins, were debased from Sterling silver (92.5%) to 50% silver.
Zero. Silver was removed from dimes and quarters starting in 1965, and replaced with copper-nickel. The only coins to have any silver during those years were half dollars, and they were debased to 40%.
It literally means your silver has become worthless. This refers to the silver content of coins being reduced and replaced with base metal, usually by the state or king. This is a recurring cycle throughout history and generally occurs after the state/king has run up massive debt, and decrees that the debased coinage must be accepted at par.
From 1965 to 1969 US half dollars were struck in "debased" silver. The outer layer is 80% silver bonded to a core that's mostly copper, for an overall content of about 40%. The price of silver is so high that even these debased coins are worth far more than 50¢ for their metal content. Please see the Related Question for more information.
I believe all Nazi 5 mark coins are 90% pure silver. Though I think some of the earlier, larger, 5 mark coins are struck in debased silver (I've seen both 63.5% silver and 50% silver listed)
Pure silver is a better conductor than copper, but is too expensive for general use. A silver coin (depending on the amount of silver) would indeed conduct electricity. True silver coins were eventually debased with cupronickel - which gives the silvery appearance of modern coins.
The only circulating coins containing silver after 1964 were half-dollars, and they contained "debased" metal with only 40% silver and the rest copper. Production of debased halves was suspended in 1969, except for collectors' coins. Circulation coinage was resumed using copper-nickel starting in 1971. Some Eisenhower dollars as well as Bicentennial quarters, halves, and dollars were struck in 40% silver for sale to collectors. In 1992 the US Mint resumed limited production of 90% silver coins; these are sold as "prestige coins" at a price that reflects the current value of silver plus minting and packaging costs.
No circulating US coin was ever made out of pure silver. It's too soft. Most contained 10% copper for hardness, and some "debased" silver half dollars contained only 40%. Please see the Related Question for details
The 1964 Kennedy half dollar. it was the only year that the coin was made of 90% silver. In 1965 the coin was "debased" to 40% silver, and in 1971 the composition was changed again to copper-nickel.
Sorry to pop your balloon, but halves dated 1965 to 1969 were "debased". The outer layers are an alloy of 80% silver and 20% copper bonded to a core with the opposite percentages, for an overall mix of 40% silver and 60% copper. As of 05/2009, the price of silver makes these coins worth about $2.50 each.
331 mean on silver
There have been six King Georges from 1714 to 1952. 1919 and 1920 were the two years when the British silver coinage was debased from 0.9250 to 0.5000 silver. Which year the change was made depends on the denomination of the coin. Prior to 1919/1920, all British "silver" coins had a 92.5% silver content. From 1919/1920 to 1946, all British "silver" coins had a 50% silver content. From 1947 to present, all circulating British "silver" coins had a 0% silver content.