Sixpences minted between 1920 and 1946 were struck in 50% silver. They therefore have a scrap value by weight of approximately £14 per Troy Ounce (as at October 2010). In mint state they have a collectors' value or numismatic value. Dealers often offer a multiplier of the face value for them i.e. at the moment 10 times their face value would be an approximation. Sixpences struck before 1920 i.e. 1919 and earlier were struck in 92.5% silver and will fetch almost double. There are rare dates of course, 1893 with the Victoria jubilee head recently fetched £5,250 in mint state due to its rarity.
New Zealand Sixpences from 1947 to 1965 were made from a copper nickel alloy.
All British 1935 Sixpences were minted at the Royal Mint London. There are no "D" Sixpences.
With the possible exception of traders tokens (with the traders business name on them), there were no "Australian" Sixpences minted prior to 1910. The only Sixpences circulating in Australia prior to 1910 were British Sixpences.
There were no 1929 Eireann (Irish) Sixpences minted.
With the possible exception of traders tokens (with the traders business name on them), there were no "Australian" Sixpences minted prior to 1910. The only Sixpences circulating in Australia prior to 1910 were British Sixpences.
There were no New Zealand Sixpences minted prior to 1933.
The Royal Mint did not produce any Sixpences from 1752 to 1756 inclusive.
All pre-1920 British Sixpences were made from sterling silver (92.5% silver content).
Modified coins have no collector value, any value would be associated with the bracelet.
The Royal Mint produced 6,382,793 British Sixpences.
If they are uncirculated and in mint condition, maybe £1 to £2 GBP. If they have been circulated, not much.
Nobody was Crowned in 1928 and Australian Sixpences were never issued as commemoratives.