In the Colonies and Boer Republics which became the Union of South Africa in 1910, several unofficial military decorations and medals were instituted and awarded during the nineteenth and early twentieth century.

In the first phase of the war, the Boer Republican Forces mounted pre-emptive strikes into British-held territories in Natal and the Cape of Good Hope, and besieged the British garrisons at Ladysmith in Natal and at Mafeking and Kimberley in the Cape of Good Hope.

[4] Official military recognition for the defence and relief of Kimberley took the form of two clasps to the Queen's South Africa Medal, the British campaign medal which was awarded to British and Colonial military personnel, civilians employed in official capacity and war correspondents, who served in the Second Boer War.

[2][3][7][8][9] The Kimberley Star was six-pointed, with a ball on each point and struck in silver, to fit into a 46 millimetres diameter circle.

[2][3][10] The reverse is plain and is inscribed, in relief, "MAYOR'S SIEGE MEDAL 1900" in three lines, with the silver hallmark impressed at the top of the lowermost star point.