Toward the end of the last ice age, an ancient human held a stone tool in their hand, then let it slip into the soil.

Perhaps they had used the tool to scrape a deer hide, a bone or a piece of wood. But the earth soon claimed the tool and held it hidden as the centuries passed and waves of people settled nearby.

The tool lay buried until this past October, when a group of volunteers, under the guidance of Zachary Singer, state terrestrial archaeologist for the Maryland Historical Trust, excavated an ancient quarry on what are now the grounds of St. John’s, Western Run Episcopal Church in Reisterstown.

“This was an exciting find,” said Singer. “It’s the first formal stone tool found at the site.”

Singer was looking for the remains of quarries from which the nomadic Clovis people dug chalcedony, a type of quartz. The Clovis people, who were once scattered across what is now the United States, fashioned arrowheads, spear tips and other tools from the stone.

For five days, Singer and a team of 50 volunteers embarked on the painstaking work of digging up and examining the contents of a grid of 56 “shovel test pits” near the church. Three of the pits yielded distinctive fragments of chalcedony, indicating that ancient people had operated a quarry there, Singer said.

“This hints at how much more there could be to find,” Singer said.

Retired nurse Rebecca Boykin said it was thrilling to help with the dig. A longtime parishioner at St. John’s, Boykin helped find a large shard of chalcedony shortly after arriving to volunteer.

“It does put things in perspective,” said Boykin, reflecting on the history buried around the grounds of the church she has attended for 20 years.

The site, called Piney Grove, was discovered by accident in 2001 when archaeologists from the State Highway Administration checked the land in preparation for a project to move the intersection of Butler Road and Piney Grove Road.

The archaeologists were shocked to uncover hundreds of fragments of chalcedony, ranging from slivers as small as a fingernail to fist-sized chunks. The fragments were clearly produced by human hands using the distinctive techniques of the Clovis people.

Such fragments, and stone tools, are all that remain of the Clovis people of the East Coast, said Singer, because the region’s acidic soils absorbed their bones, clothing and housing materials.

Archaeologists have had more luck studying the Clovis people in the dry, sandy soils of the Southwest.

The group’s name comes from Clovis, New Mexico, where a young amateur archaeologist found a spear point among mastodon bones in 1929. Anthropologists believe that the Clovis people crossed a land bridge between Siberia and Alaska and then proceeded south into the Americas. Although they were among the first humans to live on this continent, another group had arrived about 20,000 years earlier.

The Clovis people died out, although it’s not clear why or how.

The stone scraping tool, which was found by a volunteer, has not been washed and has been minimally handled, Singer said.

He hopes scientists will be able to study patterns of wear on the tool to determine whether it was used to smooth hide, wood or bone, he said.

Singer also plans to send the tool to a lab that could search for fragments of protein, say from an ancient deer or wooly mammoth.

Singer said he was still analyzing the objects found at Piney Grove in October, but that he hopes to return to do more field work there, although he has not yet set a date.

“We narrowed down another area to look and investigate further,” he said.

In the meantime, he’s gearing up for another archaeology project that will incorporate volunteers: a 17th-century home in Charles County.

The Rev. Thomas Clement, rector of St. John’s, Western Run, said the dig on the church grounds was a rewarding but surreal experience for the parish.

“It’s humbling, really,” said Clement. “I’m aware of the fact that 13,000 years ago, this was a center of intense activity.”