Pre-decimal stamps of Australia are those that were denominated in the old monetary system of pounds, shillings and pence. They were used as postage from the nation's independence, in 1901, until the end of the old currency, in 1965. Most Australian pre-decimal stamps bear images of native Australia flora and fauna, patriotic symbols or reigning monarchs. Many are highly prized by stamp collectors.
Look for the name "Australia" on the stamp. The name usually appears prominently in capital letters on either the top or the bottom of the stamp.
Find the denomination. Denominations occur as either numbers or text, and may appear almost anywhere on the stamp, and often more than once.
Look for the words pounds, shillings, or pence, or else the symbols or abbreviations for these amounts that appear next to numeric denominations. The abbreviation for pound is a cursive "L" with a horizontal line through it. The abbreviation for shilling is an "s;" that for penny, or pence, is a "d."
Examine the animals and plants on stamps that bear pictures of Australian wildlife. If the animal is a kangaroo, then the stamp is likely one of the earliest Australian stamps. A half-penny (1/2 d.) green stamp is worth $15 on today's market. A 1 penny (1 d.) green stamp can be worth as much as $725.
Identify the pictures of kings and queens that appear on the old stamps. If the stamp bears the image of George V, Edward VIII, or George VI, it is definitely pre-decimal. Pictures of the present Queen, Elizabeth II, may appear on pre-decimal stamps. If the Queen appears as a very young woman, then the stamp is likely pre-decimal.