Final answer:
The Sydney Mint started its operations in 1855, and it was notable for producing the first coins with a uniquely Australian design.
Step-by-step explanation:
The Sydney Mint began operations in 1855. It was the first branch of the Royal Mint outside England, established to produce gold coins from the gold found during the Australian gold rushes. The minted coins from the Sydney Mint were the first to have a distinctive Australian design, featuring a kangaroo and the word 'Australia'.
The mint produced gold sovereigns and silver coins for circulation until 1857, when it stopped making sovereigns, and closed in 1926.