2006 Royal Collection, 50c Selectively Gold Plated Silver Proof Coin Set. The Royal Birthday Coin is a celebration of the Queen's Birthday with the design symbolising the strong link between the United Kingdom and Australia. The Royal Visit Coin represents the stability of the crown contrasting with the rapid growth of Australia. Australia grows dynamically from the globe while the scope of Her Majesty's influence is reflected by the star and ripples spreading out from the United Kingdom on the other side of the world. Certificate of Authenticity is included with this set numbered 2321. Mintage 7500. Please contact Adelaide Exchange Jewellers to find out more on this item.