The Australian Kookaburra Silver Bullion Series was first introduced in 1990 when the Perth Mint produced the first issue. The silver coins have been minted every year since and their reverse designs change from year to year. The obverse design does not change and is of the infamous Queen Elizabeth II, the country of origin, Australia, and the coin's monetary value. These silver bullion coins also offer something unusual compared to typical silver bullion products; the silver coins come in different sizes for different investment levels (1oz, 2oz, 10oz, and 1 kilo). Although these coins are Brilliantly Uncirculated, they have a finish that is similar to the proof and fuses together mirrored and frosted aspects. The Kookaburra is a native bird in Australia and is known for its call, which is uncanny to human laughter. The Kookaburra Silver became a popular world bullion series and it inspired the Silver Koala Series in 2007.