Depending on its condition, between about US$0.10 (in "Fine" or circulated condition) to about $4.50 (in "Uncirculated" condition). The coin is worth about US$0.50 in "Extremely Fine" condition (which would be a coin that shows only very slight signs of wear). If the coin has been cleaned, these values probably drop by about 80-90% (i.e., don't clean your coins).
Australia has never produced a Farthing coin. Any Farthings that may have been circulating in Australia would have been British Farthings.
Modified coins have no collector value.
A farthing was 1/4 of a penny.
The last British Farthing was minted in 1956.
The farthing was last produced in Great Britain in 1956.
Farthings were not minted from silver, only bronze in 1901. If you have a silver Farthing it would be because somebody has plated it. Modified coins have no collector value.
1p
The last British Half-Farthing coin was issued in 1868.
There was no 1831 Third-Farthing coins minted. The Third-Farthing coin was produced for use in Malta.
Such a coin does not exist. The Royal Mint produced no Farthing coins in 1870 or 1871.
check sales for same at blade forum sites. would be valued more or less by condition. A past sale could give you an idea.
Farthings were made from bronze. If you have a silver Farthing, somebody has plated it and it is subsequently of no value as a collectible.