The Royal Australian Mint in Canberra started issuing one troy ounce of .999 fine pure silver legal tender coins depicting native Australian Kangaroos in 1993.  These crown sized silver dollars are issued annually.
These coins are called Uncirculatesd but are really reverse frosted proofs.
They are popular in Australia and worldwide.  These Roo's come from the RAM in colorful cardboard presentation cards.  The coins are securely housed in a hard plastic capsule and the presentation cards are protected by a plastic sleeve.  Very few coin dealers stock these coins so they can be
very difficult to locate.  A large US modern coin firm ran a promotion on the silver Kangaroos a few years ago and they were so popular; the advertising campaign was very successful.  Two different home shopping national television networks have promoted these Australian silver dollars.  Putting together a complete date set can be a challenge.