An old 6d coin (half a shilling) was called a tanner
A Sixpence was a small predecimal British coin. Half a Sixpence was a Threepence, an even smaller predecimal British coin.
If you refer to coins, it is a decimal coin, as opposed to a predecimal coin, that is currently in circulation.
The British predecimal Halfpenny, Penny, Threepence and Sixpence did not have an equivalent coin in decimal currency.
It was once referred to as a "Half-Shilling". In British slang it was referred to as a "Tanner". In Australian slang it was referred to as a "Zack".
The British Sixpence, known in slang as a "Tanner", also had a variety of other names derived from "Tanner" courtesy of Cockney rhyming slang. These included, Suzy Anna, Goddess Diana and Lord of the Manor.
There was no 1970 British Crown (Five Shilling) coin minted. The last British predecimal Crown (Five Shilling) coin to be minted was in 1965.
The English sixpence was also known as a half-schilling or a tanner. The British coin was worth 1/40th of a pound sterling. The artwork for the coin was designed by John Sigismund Tanner, which explains the nickname of tanner for the sixpence.
Assuming you refer to the predecimal Sixpence, it was written as 6d. The lower case "d" is the symbol for Penny taken from the Roman coin the Denarius.
I have been unable to find a comprehensive listing of Australian predecimal coin mintage figures on the internet, but the average coin catalogue should contain the figures you are looking for. Your local library may have one of the following coin catalogues specialising in Australian coins - "Pocket Guide to Australian Coins and banknotes" by Greg McDonald. "Renniks Australian Coin & Banknote Values" edited by Ian or Alan Pitt. or "The Standard Catalog of World Coins".
It would depend on what type of coin it is and what country it is from. It is very possibly a mintmark if it tucked away and not highly visible. A "P" on predecimal British Sovereigns and Half-Sovereigns would indicate that it was minted at the Perth Mint.
No. All British predecimal coinage is no longer Legal Tender. The 1965 British Crown is probably worth more as a collectible coin.
It can be created by giving a cowhide and one coin to a tanner. A tanner can be found in Al-Kharid, the Ranging Guild, and the Crafting Guild.