Rio's interest in the area has sparked a stampede into adjacent lots by other explorers, who see Rio's aggressive activity as an indicator of a highly promising find.
Mining vast untapped reserves of bauxite, phosphate, gold, copper and uranium is key to the Saudi Arabia's efforts to diversify its economy away from hydrocarbons.
Britain's High Court quashed the government's rejection of the new mine on the grounds that the minister did not provide adequate evidence for his decision.
SQM said the previously announced delays were partly offset by high prices and 25% growth in demand in 2018 on sales to producers of electric vehicles.
Xinfa Group won't have to cut metal production in its home city of Liaocheng this winter and will only have to reduce alumina output by 10% for two months.