The two dollar coin denomination (written as $2) was introduced in Australia in 1988, replacing the earlier banknotes. The original reverse design by Horst Hahne on circulating coins has not been changed since its introduction. The denomination is also often used to issue circulating commemorative coins with various reverses.
Apart from the circulating coinage, both the Royal Australian Mint and the Perth Mint have extensive programs issuing $2 coins for collectors (Non-Circulating Legal Tender, or NCLT), such as this one.
This coin was part of the 5-coin set Matserpieces in Silver 2000 - Coins of the 20th Century - Monarchs. The set depicts five monarchs whose effigies have circulated on Australian currency during the 20th Century. The set contains:
2 Dollars with Queen Victoria (this coin)
20 Cents with King Edward VII
20 Cents with King George V
50 Cents with King George VI
20 Cents with Queen Elizabeth II - Mary Gillick effigy
All of these coins have the Fourth Portrait of Queen Elizabeth II by Ian Rank Broadley on the obverse - which also shows the value and denomination; on the other side, they have a historic obverse depicting one of the monarchs and carrying his/her legend, in Latin language as was the practice on pre-decimal coins. Thus, they have the curious appearance of having two obverses, although technically speaking the "historic" side is a commemorative reverse in this case.
Actual mintage of the set was 10,412 from an initially announced limit of 15,000.
The coins are made of 99.9% silver and were issued in Proof FDC grade only. No coins of this type were released into circulation. | 
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