Archaeologists and researchers lead a dig in an empty lot at 3324 Dent Place NW to search for the remains of Yarrow Mamout, a freed slave who became a 19th-century Georgetown celebrity. (Katherine Frey/The Washington Post)

Mia Carey sinks a shovel deep into the heavy reddish soil of a bleak, empty lot in upper Georgetown.

She stands up holding a bone. “It’s a pelvis,” she announces with a smile, holding it next to another bone to show how they fit together. This discovery is probably from a small mammal, maybe a goat or a sheep. It’s not the thing she’s looking for in her summer-long quest.

She’s looking for the bones of Yarrow Mamout.

Yarrow Mamout was something of a local celebrity in early 19th-century Georgetown. Taken from Africa in 1752 and sold into slavery, he eventually gained his freedom and made himself into a comfortable homeowner and something of a local financier. A Muslim, he prayed toward Mecca in the southeast corner of his snug plot of land and walked the streets of the village, singing chants that were probably from the Koran. He could read and write in Arabic.

And in his later years, he sat for two formal portraits, including one by Charles Willson Peale, one of the most celebrated portrait painters of the 18th and 19th centuries. But after his death in 1823, Yarrow virtually disappeared into a sleepy corner of history.

Now he may literally rise again. Archaeologists are hoping to find traces of the man — bones, a coffin or even just evidence of the home he built — on his Dent Place NW property. There’s about a 50-50 chance that he’s buried there, says assistant city archaeologist Chardé Reid, one of a handful of archaeologists and volunteers who have been working on the dig this summer. It was not uncommon for people to be buried on their property in the 19th century.

Yarrow may have stayed quietly unknown and nearly lost to history if not for the curiosity of local historian and lawyer James Johnston. In 2003, Johnston came upon a portrait of Yarrow in the Peabody Room of the Georgetown Public Library.

“I was captivated,” Johnston writes in his 2012 book, “From Slave Ship to Harvard: Yarrow Mamout and the History of an African American Family.”

“Who was this black man, famous enough in his day to sit for two formal portraits, and why had I never heard of him?”

That curiosity sent Johnston on a three-year quest. What he eventually unearthed through spotty historical records was a story of almost Hollywood dimensions: a 16-year-old taken in chains from his home in Guinea in West Africa in 1752, sold into slavery in Annapolis and ending his life in a home that he built on land in Georgetown. There, he met Peale, who painted portraits of such American Revolutionary figures as Thomas Jefferson, Benjamin Franklin and George Washington.

“Yarrow was the most famous black in Georgetown in 1800, and it’s gotten lost,” says Johnston, who thinks that if Washington or Jefferson had owned the same land, it undoubtedly would have been examined closely.

The 1819 painting of Yarrow Mamout by Charles Willson Peale, one of the earliest formal portraits of a black man, hangs in the Philadelphia Museum of Art. (Alex Brandon/Associated Press)

Until very recently, a 19th-century house occupied the lot at 3324 Dent Pl. NW. But it hadn’t been lived in for years, and after a tree landed on the roof during a storm in September 2011, the house was razed.

Johnston got in touch with Ruth Trocolli, the District’s archaeologist, and the property owner eventually gave permission for an archaeological dig on the land. It was partly a strategic move: If a developer wanted to build anything new on the site and discovered bones in the process, the city’s homicide investigators would have to be called in, which could slow things down.

That happened in 2012 on Q Street NW, just a block from the Dent Place property, when a backhoe driver digging out an underground garage unearthed what turned out to be the remains of five African Americans. They probably had been buried in the vicinity of an early Presbyterian church and cemetery, land that today is Volta Park, Trocolli says.

Although Reid says the discovery was disturbing for some of the archaeologists called in to exhume the remains, it wasn’t altogether surprising. Georgetown was once home to a large African American community. Johnston says that the 1800 census counted 400 free blacks and 2,072 slaves out of Georgetown’s population of 8,144.

Since the start of the Dent Place dig in mid-June, the archaeologists have found a range of items, including a metal cuff link engraved with a tiny crown, pottery shards, clay marbles, an amber glass medicine bottle and animal bones. So far, Trocolli says, the artifacts seem to post-date Yarrow.

The archaeologists also can peer into the hole and note different shades of dirt layers, which reveal different time periods. One problem with the Dent Place site is that the dirt has been disturbed. Owners had put in an in-ground swimming pool in the 1980s and left the excavated dirt on the property, making it so that the archaeologists have had to dig through a layer of fill. Although that layer may protect the older layers of soil, it also could jumble everything together, Trocolli says.

The archaeologists are hoping to raise funds to bring in a backhoe and a remote sensing device that could send sound waves deeper into the earth to note a burial site, or nails at least.

Clockwise from top left, retired archaeologist Charlie LeeDecker, historian and author Jim Johnston, city archaeologist Ruth Trocolli, and site director Mia Carey at the dig site. (Katherine Frey/The Washington Post)

The empty lot at 3324 Dent Pl. NW where the dig is taking place. (Katherine Frey/The Washington Post)

At the moment, the archaeologists don’t know what they’ll find, though they’re hoping to come up with some of the pieces of the puzzle that was Yarrow Mamout. Muslim slaves were uncommon, Johnston says. Muhammad Fraser-Rahim, a Howard University graduate student studying Muslim influence in America, says that knowing more about Yarrow’s life could “change the narrative of how we see Islam, how we see enslaved Africans.”

In his 44 years of slavery, Yarrow was a body servant, a combination of butler and right-hand man, to Georgetown’s founding family, the Bealls, probably because he was clearly an educated man and maybe even too slightly built to be a productive field hand. Unusually, he kept his African name, or some version of it, from the Fulani tribe. Johnston writes that Yarrow was known for his brickmaking, his basket-weaving and his swimming prowess in the Potomac River.

Meanwhile, the dig has taken on some urgency. A potential buyer wants to build a three-story townhouse on the valuable Georgetown land. Trocolli, Reid and Carey, a graduate student at the University of Florida, are running the dig on a shoestring, with volunteer help. Carey is leading it, but her stint will end sometime in August, when she’ll go back to school.

Besides the time limits and the lack of funds, there’s the question of what the Dent Place dirt will ultimately yield. David Hunt, a forensic anthropologist with the Smithsonian Institution’s National Museum of Natural History, says that the District’s soil, which is both acidic and “heavy with marine clay,” could pose a problem. “Bone does not survive real well in soils around here,” he says. Within 75 to 100 years, the remains of bones could be nothing more than fragments or even just stains in the ground.

If Yarrow was buried in a shroud with no coffin, he “may not exist as a skeleton,” he says.

The portrait that launched Johnston’s quest, painted by 17-year-old James Alexander Simpson in 1822, hangs facing east in the quiet Peabody Room, on the third floor, of the Georgetown Public Library, a short walk from where Yarrow lived.

Painted the year before he died, it shows a solemn-looking man with a gaunt face who gazes into the room through heavy-lidded, tired eyes.

Compare that with the Peale portrait at the Philadelphia Museum of Art, done about three years earlier. In that one, Yarrow looks straight ahead with a slight smile on his face. His nose is long, and there are patches of a beard on his lower chin. He’s wearing a striped cap and several layers of clothing, and the sun hits his face on the right side. Peale recorded the experience of painting Yarrow, saying that the subject’s “good temper” must have been what had contributed to his longevity. He was believed to be in his mid-80s at the time of his death.

When Georgetown librarian Jerry McCoy traveled to Philadelphia to see the portrait, he says: “I stood there and got teary-eyed. I felt I was standing in front of the man.”

Now, archaeologists would like to go a step beyond the two portraits and find something tangible that they could connect to Yarrow. “One of the strengths of archaeology as a discipline is that it gives us the ability to find out things about people who didn’t enter the historical record,” Trocolli says.

Yet she’s not entirely sure that she wants to find his bones. She’d like him to rest in peace.

Debra Bruno is a freelance writer in Washington.