Dalian iron ore set for seventh quarterly gain on May rally

* Dalian iron ore up about 20% in June quarter

* SGX iron ore, spot price supported at $200/T levels

By Enrico Dela Cruz

June 30 (Reuters) - Dalian iron ore was set on Wednesday for a seventh straight quarterly gain even as a slump in Chinese steel mills' profit margins weighed on prices in the final trading sessions of June.

The most-traded iron ore for September delivery on China's Dalian Commodity Exchange ended the morning session 1.8% lower at 1,153 yuan ($178.58) a tonne, down 15.1% from a record high scaled on May 12.

Dalian iron ore, however, was set to close the quarter with a gain of nearly 20%, helped by its record-setting rally in May.

Robust raw material demand in China, the world's top steel producer, had propelled iron ore prices to record highs in a rally also spurred by what Chinese authorities had described as excessive market speculation.

Costly raw materials combined with softening demand for steel products in China are now weighing on steel producers' profitability, analysts said.

"Steel prices have dropped sharply from May record highs," said Robert Rennie, head of financial market strategy at Westpac. "With coking coal at two-year highs and iron ore close to record, steel mill profitability has collapsed."

On the Singapore Exchange, iron ore's most-active August contract , however, held firm at $200 a tonne by 0423 GMT.

The spot price of benchmark 62%-grade material was $215 a tonne on Tuesday, according to SteelHome consultancy data.

"When we scale (China) iron ore inventory to slightly softer steel production or imports, the iron ore price looks increasingly out of line," Rennie said.

"If these trends of weaker steel production continue through the summer, then that argument becomes even more compelling."

Construction steel rebar on the Shanghai Futures Exchange

edged up 0.1%, while hot rolled coil gained 0.7%. Stainless steel added 0.9%.

Dalian coking coal dropped 0.9% and coke slumped 2.3%.

(Reporting by Enrico Dela Cruz in Manila; Editing by Subhranshu Sahu)

((enrico.delacruz@thomsonsonreuters.com))