From 1825, the official money of the Cape Colony was British and in 1866, Sovereigns struck at the Sydney branch mint were also made legal tender. A year later, Natal made Australian Sovereigns and Half-Sovereigns legal tender, although British coinage was not made the official currency of this area until 1882; three years later, in 1885, it was introduced in Bechuanaland. The end of the Boer War in 1902 led to the annexing of the Transvaal and Orange Free State into the British Empire and in 1910, the Union of South Africa was formed. Initially, British coins formed the basis of the new Union’s currency and British gold coins were legal tender to any amount. A branch mint was later established in Pretoria where striking began in 1923. Production peaked in 1928 when more than 18 million Sovereigns were struck. The origin of these coins is denoted by the mint mark ‘SA’.