Where do those medals come from?

Metals for Medals (2:00)

Ever wonder where the metal for the Olympic medals comes from? Go behind the scenes and get the scoop. (2:00)

The original Olympians kept victory recognition simple. The ancient Greeks, dating as far back as 776 B.C., bestowed olive wreaths upon the winners' heads. Medal presentations came hundreds of years later, in 1896, but the moment has remained poignant.

And over the next few weeks through September, 4,700 more medals -- gold, silver and bronze -- will be awarded to Olympic and Paralympic athletes across 805 victory ceremonies. The top three finishers in each event will stand on a podium as an official walks toward them, holding that precious prize engraved with the year, discipline and commemorative design specific to the London Games, and will inadvertently bow down toward the gleaming, meticulously crafted circle.

Viewers from around the world may notice the medal's brilliant shine. Or perhaps they'll wonder at the gold medal's composition, which is mostly silver (92.5 percent silver, 1.34 percent gold and the remainder copper).

Years from now, the medal might end up on a shelf or passed around amongst a class of schoolchildren until one of them drops it, leaving a permanent dent in the medal's side (the latter actually happened to Olympic swimmer Dana Vollmer's gold medal from 2004). The medal might inspire an athlete to recall the stories of his or her 2012 triumph, detailing how the hours, days, weeks, months and years of hard work led to this prize, as their fingers simultaneously tarnish the shine.

But in those first public moments on the podium, the medal will be perfect and radiant, hanging near the athlete's heart as tangible proof of his or her mark in sporting history.

It's a far cry from the medals' origin, in the depths of a vast canyon thousands of miles away.

Diving into the medal ore

The 27,000-acre open-pit mine at Kennecott Utah Copper, astronauts say, is the only U.S. man-made object visible from space. Stretching almost three miles across and three-quarters of a mile deep (with another 300 feet of depth scheduled to be added by 2018), the mine is 28 miles southwest of the Salt Lake City International Airport. The mine is open 365 days a year, 24 hours a day, providing 13 percent of the country's copper needs and, this year, close to 99 percent of the metal behind the 2012 Olympic medals.

From the visitors center viewing deck, the mine resembles a giant inverted sandcastle, with row after row of benches (layers of cleared and plowed earth) stretching to depths almost beyond view. Traveling from the very bottom of the mine to the top can take over an hour.

Two Mormon brothers discovered copper ore in the Bingham Canyon in the mid-1800s and the original Utah Copper Company was created in 1906. Today, Kennecott, which is owned by international mining giant Rio Tinto, produces 300,000 tons of refined copper each year, as well as 400,000 ounces of gold, 4 million ounces of silver and 25 million pounds of molybdenum. The Kennecott operation employs 2,300 people, with hundreds more working at one of Rio Tinto's nearby offices.

Headquartered in London with operations in Australia, Asia and now Mongolia, Rio Tinto is one of the world's largest mining corporations. This isn't its first Olympic medal rodeo; Kennecott also created the 2002 medals for the Salt Lake City Winter Games.

Kennecott CEO Kelly Saunders credits the repeat honor, in large part, to sustainable development projects. "They saw our business as having a strong story around sustainable development," Saunders said. "In our community, we work very hard to build alliances with every organization that has a strong focus on sustainability."

While views conflict over the environmental hazards of mining (a coalition of environmental groups filed a federal lawsuit against Kennecott Utah Copper in December 2011, claiming a violation of the Federal Clean Air Act; more recently, international groups have called for a protest of Rio Tinto as the Olympic medals provider because of the corporation's treatment of the environment, its workers and public health), Rio Tinto and Kennecott said they have worked toward safe practices and offering a variety of employment opportunities to local residents.

And despite the protests, being the medal provider for the 2012 Games is one of those opportunities.

The process begins with nine drills working inside the canyon, digging holes 55 feet deep that are then filled with close to 1,200 pounds of explosives. Twice a day, the explosives are detonated, loosening the rock in preparation for massive electric shovels. Inside several of those explosions lay the ore for the Olympic medals.

The rocks are unearthed by one of the mine's seven oversized shovels, which resemble a transformer from a Michael Bay film. The shovel's movements, back and forth, up and down, filling one truck bed and then another, are surprisingly fluid given its size and the fact it can haul 85 tons in a single scoop. The mine's fleet of 88 trucks is in constant motion, assigned to a specific shovel via a systems operator and electronic computer system.

While the trucks look like toys compared to the shovel, each one is larger than a two-story house. Anyone entering a truck has to climb a 30-foot metal staircase located on the front. Hard hats, gloves, eye protection and steel-toed boots are required; ear plugs are recommended. Standard-sized pick-ups driven around the property must fly flags high above their roofs to indicate their presence in this canyon of vehicles-on-steroids.

The shovel loads each truck with 280-340 tons of rock and waste. The driver I rode with told me that while the weight-bearing limit is set at around 320 tons, the shovel sometimes exceeds that number (ours measured at 337 tons). After hearing the requisite "go-ahead" honk from the shovel operator, we carted our load to the aptly-named crusher.

The crusher, a towering 60 feet by 109 feet, pounds the rock chunks (an average of 136,000 tons per day) into pieces around 10 inches in diameter (Step 2 for the medals). The stream of diminished rock is then fed into a conveyor belt carrying the contents five miles across the mountain to the concentrator.

On the day I visited, the concentrator was undergoing annual maintenance, so the conveyor belt and concentrator operations were turned off. Typically, the belt moves at a speed of 900 feet per minute, meaning the ore's journey from crusher to concentrator takes, on average, about 28 minutes.

Concentrating, the process of gathering the valuable minerals from the ore, happens through a grinding mill and separation process. During concentration, the ore pieces are whittled down in size until they're small specks with the consistency and size of powder (Step 3 for the medals).

That mixture then moves into flotation cells, where the ore is mixed with reagents and the valuable minerals float over the sides (the concentrate). The leftover particles, known as tailings, sink to the bottom before flowing through a pipeline to a storage impoundment.

The concentrate travels through a 17-mile pipeline to a smelter for further processing before moving on to the refinery.

Inside the refinery, the copper is separated from the precious metals and recovered. The multi-day process results in copper cathodes that are 99.99 percent pure. Small, rounded sample "buttons" are taken from the cathodes to ensure their quality. While Kennecott intended to ship the copper for the Olympic medals in cathode form, "the Royal Mint isn't set up to take [these] cathodes, so we took the samples and shipped those small buttons," refinery general manager Anna Wiley said.

The other impurities, including the silver and gold, drop off during the 10-day process. The residue from that solution is moved to an adjacent precious metals plant, where it undergoes several steps before being separated and shaped into bars. I wasn't allowed inside the precious metals plant (for security reasons), which produces approximately 460,000 ounces of gold and 4,150,000 ounces of silver per year.

Finally, starting in February 2011, Kennecott shipped the metals to the Royal Mint in three shipments (the last in July 2011) to begin the next phase of development.

"The workers were pretty excited and I was, too," Wiley said of being a part of the Olympic medals process. "It's a really nice connection to have. The guys put a lot of effort in to collect the metal and I think they're really proud of the fact that we can say it's our metal that's in the medals."

"When you think about the process it goes through, to be a part of that at the very beginning is a wonderful feeling," said 65-year-old Kennecott mine operator Lee Hudson. "You'd never think that you dig dirt and through the process you get to the finest metals in the world."

Hudson, a championship softball player who has never been to London, was one of four Kennecott employees selected for Rio Tinto's Olympic Heroes program. During the past year, staffers nominated their fellow co-workers to be sent, along with one guest, on an all-expenses paid trip to the Olympics.

The next steps

The metals arrived at the Royal Mint and were subsequently shipped to Madrid, Spain, and Birmingham, England, to be cast. Royal Mint quality assurance manager John Bunney traveled to Spain to oversee the process. The 59-year-old has worked at the mint for 36 years, but this was his first experience with Olympic medals.

The mint assigned a team of 30 employees to work solely on the medals. Since each medal undergoes close to 22 processes, the employees, known as the Athena Project Team, brought different specialties. Bunney said they calculated that each medal took approximately 10 hours of working time.

The casted discs returned to the mint in October of last year and its staff began to work on the gold medals first before moving on to bronze and silver. Each gold medal weighs 416 grams (85mm diameter, 7mm in thickness) and has to have at least 5.5 grams of gold. Because they're predominantly silver, the gold plating-process gives the medals their golden look.

The medals are then struck, similar to making coins. While the Winter Olympic medals design changes each time, the Summer Olympic medals usually depict the winged goddess of victory, Nike, on the front. Because of the intricate detail of this year's design, the medals needed three striking operations. With each strike, a portion of the image is produced; the medal is softened in the furnace and then it's struck again. The entire striking process took close to three weeks.

Any imperfections or marks are removed from the medals through a heated acid solution process. Then the finish is added; each medal is blasted with a sand material at a very high pressure. A burnishing process, where the medal is given a straight gloss, rounds out the finishing.

The clasps for the ribbons are then attached. "That's another difficult process because these are very heavy medals, so we had to make sure the clasp, the mount, was going to be secure," Bunney said.

Next, the medals are individually inspected and hallmarked to verify the quality before being engraved with the discipline. The gold medals are then plated and weighed again. The medals are coated in a clear lacquer, applied in an oven set at 130 degrees, to prevent the medals from tarnishing.

Afterward, the ribbons are sewn on to the medals, one at a time. Each ribbon has to be an exact length and stitched through the mount in a precise way because the five Olympic rings must be .19 inches (5 mm) above the top of the medals. The mint completed its work in April before moving on to create medals for the Paralympics.

Like its Kennecott colleagues, the mint staff enjoyed the medals' creation process.

"Even though I've been at the Royal Mint for a long time, this is a challenge which is unprecedented," Bunney said. "It's been hard work, but so interesting because we've learned new methods of manufacture, new types of processing with the finish. These are by far the biggest, heaviest medals ever, and we take pride in that fact."