LONDON, July 30 (Reuters) – Copper prices fell on Monday as investors shrugged off a potential strike at the world’s largest copper mine and focused instead on economic data this week expected to show slowing growth in top metals consumer China. Benchmark copper on the London Metal Exchange (LME) was down 1.5 percent at $6,204 a tonne at 1023 GMT, echoing a 1.4 percent fall on the Shanghai Futures Exchange. Concerns over the impact of trade tensions on metals demand have helped push copper down 15 percent on the LME since early June. On July 19 it hit a one-year low of $5,988. Trade concerns were still driving the market, said ING analyst Oliver Nugent. “You had a couple of stable days last week and then the market started (on Monday) with a wave of profit taking out of China, restoring the downward sentiment,” he said.

CHILE STRIKE: Workers at Chile’s Escondida copper mine rejected a final contract offer and on Saturday began a vote on strike action that will continue through the middle of this week. Last year, a 44-day strike at the mine pushed copper prices sharply higher.

CHINA DEMAND: Fears of supply interruptions were, however, matched by worries of weaker demand in China, where factory sector growth is expected to have slowed for a second month in July. The official PMI survey is due on Tuesday and the private Caixin manufacturing PMI published on Aug. 1.

POSITIONING: Investors are betting that copper prices will continue to fall, with the net short position on the Comex exchange the largest in nearly two years.

ZINC: Benchmark LME zinc was down 2.9 percent at $2,523.50 a tonne, close to a one-year low of $2,473.85 reached on July 20.

TECHNICALS: Zinc was holding around support at the 50 percent retracement of its two year rally from 2016 to early 2018 and just above its 2017 low of $2,427.50.

ZINC SPREAD: The premium of cash zinc over the three month contract MZN0-3 was $50.50, up from less than $10 in mid-July and suggesting a shortage in nearby supply.

STOCKS: While copper and zinc stocks in LME-registered warehouses were fairly stable in July, stockpiles in Shanghai Futures Exchange storehouses fell, with copper down 25 percent at 197,068 tonnes and zinc down 50 percent at 48,135 tonnes. CU-STX-SGH ZN-STX-SGH

WARRANTS: Underlining concerns of tight supply, one entity held 50-79 percent of LME copper warrants and one entity controlled 50-79 percent of LME zinc warrants.