They date back more than 10,000 years. Small pieces of stone -- the largest just over 2 inches long -- that could help explain a whole culture.

	John Beale, Post-Gazette Melissa Diamanti, senior principal investigator for Archaeological and Historical Consultants Inc., holds a Greenbrier-type spear point from 7000-6500 B.C., found in Sproul, Blair County. Click photo for larger image.

So far, 2,001 artifacts have been found at a construction site on the edge of Blair County, near the Bedford County line, just off Interstate 99. The people who roamed Central Pennsylvania around 8000 B.C. shaped these stones for use as blades to cut meat, perhaps; or for scrapers, possibly used to separate the fur from the hide on wild game they ate.

More archaeological work will be done at the site of the 100-acre Walter Business Park later this summer, before the work to straighten a road and improve the interchange at Business Route 220 begins.

"What makes this site special is that it's so early and so intact," said Melissa Diamanti, the senior principal investigator for Archaeological and Historical Consultants, in Centre Hall, Centre County, which is doing the work. "It's rare to find a site like this in Pennsylvania."

The most easily recognizable pieces among the newly found collection are spear points -- with visibly defined curves and bases used by Native American hunters to take down their prey.

When eight representatives from Diamanti's company arrived at the site for the first time on Oct. 1, 2002, they didn't expect to find prehistoric artifacts.

But one of the first items caught in their 1/4-inch screens was a 2-inch-long spear point, dating to 7000 to 6500 B.C. It resembles the Greenbrier-type point, most often found in Kentucky and Tennessee.

Made of brown chert, a medium-quality stone in the quartz family, the point has a flat base and wide shallow notches where it would attach to a spear with sinew. It, along with the other spear points found, appears to have a feathered texture, created when the flakes of stone are knocked off during shaping. That detailed, fine work is created by pressure flaking -- pushing on the point with bone or antler tines to make flakes on the bottom side fall off, Diamanti said.

"It's a slow, meticulous process," she said.

< Tips like the Greenbrier one would likely be used on spears 4 to 5 feet long, Diamanti said.

Most of the artifacts found at the site date back to 8500 to 6000 B.C. or the Paleoindian and Early Archaic periods. "That's pretty exciting. It's rare to find things that early at a site," she said.

The oldest piece researchers found dates to 8500 to 7400 B.C. It had been reshaped from being a spear point to a drill, Diamanti said -- early evidence that Native Americans recycled their worn-out tools and found new uses for them.

Most of the artifacts have been found in a small area -- about 75 feet by 100 feet, right up against where the road project will be.

Of the 2,001 prehistoric pieces found, there are 12 spear points, 16 blades and six scrapers. The rest of the specimens collected are flakes that were knocked off as the tools were shaped.

All those flakes mean that the Native Americans were making their tools right along the ridge there in Blair County, just a few feet away from an industrial park that houses a Sheetz distribution center. Diamanti guesses that the Native Americans traveled in groups of eight to 12 and camped at each location for a few days to a few weeks before moving on. Typically, they would camp within a couple hundred feet of a river, within the flood plain, she said. The site in Sproul is different, though. It's at the base of a ridge, high above the flood plain.

"It is exciting to find a site that's not like a hundred other sites you've found," Diamanti said. "It's the ones like this one that make the job most interesting."

Dating artifacts can be done in two ways -- by radiocarbon dating, which uses scientific analysis on carbonized materials like charred seeds or burnt bone; or by comparing the artifacts to those discovered at other sites that have used carbon dating.

Diamanti is using comparison at the industrial park site, with help from the reference book, "Stone Age Spear and Arrow Points of the Mid-continental and Eastern United States."

After the excavation is completed, more scientists will arrive at the site to study the landscape and help determine what the environment was like there 10,000 years ago.

Marty Marasco, the president and CEO of Altoona Blair County Development Corp., said the industrial park project was initiated three years ago. The Sheetz distribution center occupies 60 acres of the development, and Marasco hopes to find tenants for the other 40 acres soon.

Though the finding of a Native American site has held up the project by about a year, at least work will be allowed to continue after the excavation, he said.

"They say it's one of a kind in this part of the country, and it had to happen to us," Marasco said.

For any project involving federal funding, an archaeological and historical study must be done of the land to determine if there are historically significant items that will be affected by the work. This one started in October 2002 when archaeologists identified the site. They later found it to be important and began recovery of the artifacts in November 2003. The work is on hold again, awaiting a signed memorandum of understanding among all the interested parties. That agreement outlines the archaeological plan to excavate the site.

Once the excavation of the site is completed, construction work can begin.

In all, the archaeological work at the site will cost about $500,000.

"We feel digging at the site is worth the extra money and extra time in delaying the project," Diamanti said. "We can actually learn new information from this site."

Some of the things that might be revealed are what types of animals the spear points were used on -- if there is any blood residue found on them -- and what kind of cutting motion the Native Americans used with their blades.

At the site, archaeologists dig in sections that are 1 square meter and then meticulously sift through dirt, vegetation and other, natural rocks. This excavation is rather shallow, with most of the artifacts found within the top 10 inches of plowed soil.

"Unplowed sites are extremely rare in Pennsylvania," she said.

What's most impressive about the site, Diamanti said, is that other Native Americans didn't camp in the same spot years, or generations, later, leaving behind more recent tools.

Near that area, though, archaeologists in the group discovered two cooking pits, dating to 1200 B.C. and 1200 A.D. Diamanti hopes to find more cooking pits that match the period when the spear points were made.

Eric Scuoteguazza, a regional archaeologist with PennDOT, said the site at the Walter Business Park has continental significance.

They were lucky to find it, he said, especially when many are overlooked or not examined fully to determine their importance.

Though a part of the site will be destroyed by the road project, the artifacts found there and the value of them will not. The artifacts will be studied, analyzed and eventually displayed. By doing that, he said, the information revealed by them is never really lost.

"Archaeology is a destructive science," Scuoteguazza said. "One you remove it, you can't put it back."