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.
Q: From 1530 a royal act restricted all shipments of coal from Tyneside to Newcastle Quayside, giving a monopoly in the coal trade to a cartel of Newcastle burgesses known as the Hostmen. This monopoly, which lasted for a considerable time, helped Newcastle prosper and develop into a major town. The phrase taking coals to Newcastle was first recorded contextually in 1538. The phrase itself means a pointless pursuit. In the 18th century American Timothy Dexter, an entrepreneur, widely regarded as an eccentric, defied this idiom. He was persuaded to sail a shipment of coal to Newcastle by merchants plotting to ruin him; however his shipment arrived on the Tyne during a strike that had crippled local production; unexpectedly he made a considerable profit.
A:
What did a 1530 royal act restrict shipments of?