This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: With the union of the crowns of Castille and Aragon (1479), the use of Spanish gradually became more prestigious. Starting in the 16th century, Catalan literature experienced a decline, the language came under the influence of Spanish, and the urban and literary classes became bilingual.

Answer: When were Castille and Aragon united?

Question: In total, 156 prisoners have been either acquitted, or received pardons or commutations on the basis of possible innocence, between 1973 to 2015. Death penalty opponents often argue that this statistic shows how perilously close states have come to undertaking wrongful executions; proponents point out that the statistic refers only to those exonerated in law, and that the truly innocent may be a smaller number. Statistics likely understate the actual problem of wrongful convictions because once an execution has occurred there is often insufficient motivation and finance to keep a case open, and it becomes unlikely at that point that the miscarriage of justice will ever be exposed.

Answer: Between 1973 and 2015, how amny prisoners were acquitted or received pardons or commutations of their death sentences due to possible innocence?

Question: With the gold rush largely over by 1860, Melbourne continued to grow on the back of continuing gold mining, as the major port for exporting the agricultural products of Victoria, especially wool, and a developing manufacturing sector protected by high tariffs. An extensive radial railway network centred on Melbourne and spreading out across the suburbs and into the countryside was established from the late 1850s. Further major public buildings were begun in the 1860s and 1870s such as the Supreme Court, Government House, and the Queen Victoria Market. The central city filled up with shops and offices, workshops, and warehouses. Large banks and hotels faced the main streets, with fine townhouses in the east end of Collins Street, contrasting with tiny cottages down laneways within the blocks. The Aboriginal population continued to decline with an estimated 80% total decrease by 1863, due primarily to introduced diseases, particularly smallpox, frontier violence and dispossession from their lands.

Answer:
When was the gold rush over in Melbourne?