When one of Dr. Susan Mulholland's students finds an artifact, it's cause for celebration.
"I start dancing around," Mulholland said. "It's exciting."
Mulholland, an adjunct assistant professor in anthropology at the University of Minnesota Duluth, leads a summer Field Research in Archaeology course for UMD undergraduates.
At their excavation site, along a stream north of Duluth, she's been dancing a lot lately - her three-student crew finds several items per day. Some could be nearly 10,000 years old.
"The number of things we have found has surprised me a little bit," said Käthe Trahan, a junior criminology and anthropology major at UMD and member of this summer's crew.
Through the meticulous excavation of a 1-meter by 1-meter hole, called a unit, the students have uncovered flakes, or pieces of rock left behind after striking rocks together to shape tools; discolored soil suggesting a hole was dug there for a campfire; and small pieces of charcoal, further evidence of a fire. Charcoal is a good find for archeologists; its age can be determined through carbon dating.
For the last several years, ever since erosion revealed the first items, UMD crews have found larger artifacts like a broken knife blade or spearpoint, a stone tool flaked on both sides and a scraper.
Some of what they find can be deceitful - rocks resembling flakes. If it has smooth edges and lacks a bulb of percussion, which forms near the point of impact when forcefully striking rocks against each other, then it's just a piece rock, not a flake
"It's a wannabe, it's a teaching tool now - gotcha," Mulholland said, holding up a pseudo flake.
Flakes, charcoal and broken tools found by the crew are what was thrown out, lost or left behind by people thousands of years ago.
"Most archeology is just looking at garbage," Mulholland said.
But for her students, that doesn't matter.
"It's holding a piece of history that's been here for - who knows how long," Trahan said.
Madeleine Hoffman, a senior anthropology major at UMD, likes that feeling too.
"It's very powerful ... just knowing somebody used this tool thousands of years ago to maybe cut the skin off an animal or some other purpose," Hoffman said. "It's just really, really neat."
Finding those flakes or bits of charcoal takes time.
Leaning over the hole bordered in pink string, the students sat on yellow foam pads and gently scraped away a layer of soil from the bottom of the square hole, two intersecting lines in the dirt dividing the unit into four equal-sized squares.
Scraping only 2.5 centimeters down into the ground at a time, the crew placed the soil from each quadrant into four separate bins. Then they'll dump it through a quarter-inch screen, letting the dirt fall through, leaving only objects too large to fit through. If they're lucky, that process will reveal a few flakes and pieces of charcoal.
When they do find something, it's bagged, labeled and recorded.
"Go bag that sucker," Mulholland said to her students after examining a flake.
Paperwork is filled out for each layer, each quadrant and any item bagged.
It's taken a week and a half to get 25 layers, or 50 centimeters, deep.
"You need a lot of patience," Trahan said.
"It's not like Indiana Jones," added Slade Gulan, a junior anthropology and history major.