Manufacturing expansion in China, the world’s biggest metal consumer, has sent the price of copper to a six-month high with inventories shrinking.

The HSBC Holdings Plc and Markit Economics got a Chinese factory measure for December of 50.5 while the statistics bureau and logistics federations put the number at 51, both of the indicating a clear expansion on Chinese manufacturing. At the same time, Copper piles on the London Metal Exchange dropped for the 41st consecutive season in a row, the longest running streak in almost a decade.

But the rise in the metal’s price seems precarious as the whole business depends mostly on China. As Herwig Schmidt, head of sales at Triland Metals Ltd. in London, put it: “If China suddenly catches a cold, we will see everything go somewhere quite a bit lower.”

Although Chinese exports experienced a drop last month, the country’s imports of refined copper increased in November while shipments were at their highest in 19 months in September.

The inventories of copper at the LME fell to their lowest lever since last January to 365,700 tons, while stockpiles on the Shanghai Futures Exchange are the lowest in nearly one year.