(Corrects in fourth para to say that Dec soy imports hit their third-highest monthly total, not the second-highest)
BEIJING, Jan 12 (Reuters) - China's commodities buying spree eased slightly in December, with copper, iron ore and crude oil imports all falling from bumper levels a month earlier, the latest sign that Beijing's anti-smog crackdown is slowing industrial activity.
The drop contributed to an overall deceleration in China's imports and exports, which highlighted ebbing momentum in the world's second-largest economy.
Natural gas and coal imports meanwhile surged last month, the General Administration of Customs said on Friday, amid fuel shortages that left millions of homes freezing across the north of China and factories in the south roiled by forced cutbacks.
Imports of soybeans hit their third-highest monthly total in December of 9.55 million tonnes, and a record 95.54 million tonnes for the year.
Shipments of oil, gas, copper concentrate and iron ore all also set new record highs in 2017, as the world's top consumer of commodities continued to scoop up lower-priced raw materials to feed its vast heavy industry.
"I think the slowdown is really mild mostly in line with seasonality," said Victor You, an analyst with CLSA in Hong Kong, who tracks China's iron ore, coal, copper and copper concentrate imports, as well as its exports of steel products and aluminium.
"If we look at an annual basis then iron ore is at a new annual high," he added, also noting a "10 percent plus pick-up" in aluminium exports for the second month in a row.
Iron ore futures on the Dalian Commodity Exchange dropped 2.1 percent to 544 yuan ($84.28) a tonne on Friday.
China's crude oil imports were down 12 percent last month, albeit from near-record levels above 9 million barrels per day in November, weighing on futures prices on Friday.
Buying eased in December as refiners and fuel distributors drew on inventories after hefty stockpiling in the previous month, said Seng-Yick Tee, analyst with SIA Energy.
December oil products exports hit a record 6.17 million tonnes, as refiners churned out more fuel than the country could absorb. This has contributed to a fall in Singapore refinery profit margins <DUB-SIN-REF> to below $6 per barrel this month, their lowest seasonal level in five years.
GAS AND COAL: STANDOUTS
Gas imports hit a new annual record, smashing the previous high by 20 percent, on the back of a massive gasification drive that gained momentum late in the year as temperatures in northern China dropped.
With the plan to heat millions of homes with the fuel proving overambitious, and leading to shortages, there was also a 3.2 percent month-on-month boost in coal imports in December after the government eased restrictions on imports to keep the country warm. ($1 = 6.4550 Chinese yuan renminbi)
(Reporting by Tom Daly; Editing by Josephine Mason and Christian Schmollinger)