FAIRBANKS — Gold prices are up and so is the quantity of rock that has to be processed at the Fort Knox mine to retrieve every ounce.

The mine produced more than 800 ounces of gold a day over the summer, extracting an ounce from every 90 tons of rock.

The mine is still a heavyweight producer for Kinross, a Canadian company that operates 10 mines around the world. The firm reported total revenues of more than $1 billion in the quarter that ended Sept. 30, a company record states.

Kinross reported adjusted net earnings of $273 million for the quarter, up from $117 million a year ago.

At Fort Knox, the company processed lower-grade stockpiled ore in the third quarter, so its production is down about 32,000 ounces of gold from the same period in 2010.

Tye Burt, president and chief executive officer, said in an earnings call that margins per ounce of gold exceeded $1,000 for the first time from its worldwide operations.

At Fort Knox, Kinross extracts gold by grinding rocks in an ore mill and treating lower-grade rocks with “heap leaching,” a process to remove gold by covering them with a diluted cyanide solution.

The rocks are placed on an impermeable pad and the gold-bearing solution is collected to remove the precious metal.

“The heap leach at Fort Knox continues to perform well. Production was slightly lower compared to the second quarter due to processing of lower grade stockpiles,” Brant Hinze, chief operating officer, told stock analysts this week.

In 2009, Fort Knox began using heap leaching on the large volume of low-grade rocks that had been stockpiled over the years because it was not economical to run them through the giant rock-crushing mill.

“The heap leach facility now allows the mine to process these low-grade materials economically, as well as zones of lower-grade ore in the mine. It thus has increased overall production, and extended the life of the mine,” said Kinross spokesman Steve Mitchell.

Fort Knox is processing ore in its mill that contains about half a gram per metric ton of rock, down from nearly a gram per metric ton a year ago. A metric ton contains about 2,204 pounds.

The combination of heap leaching and processed ore led to recovery of an ounce of gold for every 90 tons (or 82 metric tons) of rock.

 The company placed nearly 6 million metric tons on its heap leaching pad during the third quarter. The total for the first nine months of the year is about 13 million metric tons.

The production cost at Fort Knox for the third quarter was $712 per ounce, up from $678 in the second quarter and $501 for the third quarter a year ago. The increase is mainly a result of processing rocks that don’t contain as much gold.

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PERFECT TIMING: Along with most of the rest of the country, we will turn back the hands of time early Sunday.

As we take the fallback position, we have all sorts of electronic communication devices to confirm we are doing so at the appropriate time.

When Fairbanks first appeared on the map, and for many years thereafter, it was a far more difficult proposition. In fact, community disputes broke out about where the big hand the little hand should be set.

In late 1908, business leaders, miners and others approached the Northern Commercial Co. in the fall and asked that Fairbanks go on winter daylight saving time.

A decade before the U.S. Congress approved daylight saving for the summer, Fairbanks pioneers thought what they could really use was some daylight saving in the winter.

The N.C. Co. manager, Volney Richmond, said he would do whatever the residents wanted. He switched the whistle schedule in the fall of 1908 so it sounded one hour later, allowing people to set their clocks by it.

As a city on the leading edge of the winter daylight saving time movement, Fairbanks found it wasn’t easy to get the timing exactly right.

The Tanana Valley Railroad, which served the mining camps all the way out to Chatanika, observed the change, as did businesses and the city. The plan might have worked for the long run, but the court system refused to change its clocks.

“At the present time, the trouble resulting from having the courthouse one hour behind the city has been painfully apparent, in the attendance of those who are apt to be fined if they fail to get to court when needed,” the newspaper said in December.

After a couple of months, time-conscious individuals circulated a petition and the N.C. Co. changed the whistle schedule and ended the two-time-zones-in-Fairbanks era.

Columnist Dermot Cole can be reached at cole@newsminer.com or 459-75309.