Historic Tampa home made of rare stone to be restored
The stones were dredged from the Hillsborough River for 712 S. Edison Ave.

By Paul Guzzo
Tampa Bay Times
Published: Jan 31, 2024

TAMPA — More than a century ago, a home was constructed with stones dredged from the Hillsborough River.

Located at 712 S. Edison Ave. and now one of the buildings that make up the Hyde Park Historic District, the house is one of just two buildings made with those rocks. St. James House of Prayer Episcopal Church at 2708 N. Central Ave. is the other.

The church has maintained its structure. Previous owners of the home did not.

But restoration of the house has begun thanks to 712 S. Edison Ave. LLC, which purchased it in 2022 and, according to state records, is overseen by Drew Peloubet.

The two-story, 3,300-square-foot home’s foundation needs to be shored up. It needs a new roof, which is not made of stone. The wood floor on the first story, which sags beneath the weight of a single person, will be replaced. And, most importantly, the mortar will be repaired to keep the house’s unique stones from displacing.

“It has to be saved,” said Lane Mari, vice president of GM Construction, which is restoring the home to be sold later this year. “They don’t make them like this anymore.”

The scarcity of the rock used is what’s so hard to replicate.

“It would be almost impossible to replicate” the house and church, said Sam Upchurch, who formerly chaired the University of South Florida’s Geology Department. He said it would be hard to find similar rocks.

A year ago, when St. James House of Prayer Episcopal Church celebrated the 100th anniversary of its building, the congregation’s leaders were curious what type of stone was used in the construction. Mari wanted to know about the house, too.

All they had to do was ask Upchurch, who once studied the construction of the church as part of the application for its listing on the National Register of Historic Places.

The rocks, he said, are known as chert, which is composed of the mineral quartz. Chert was once used by Native Americans for tools and weapons and today for jewelry and arrowhead replicas.

“Chert is everywhere in central Florida,” said Roger Dawson, a project manager with Environmental Consulting & Technology. In Florida, chert “has its origins as the shells of sea critters that covered the peninsula while underwater.”

Today, chert is most common around phosphate mining areas.

But the chert pulled from mining quarries would likely be cream colored and void of markings, while the rocks that make up the house and church are shades of brown, gray and white.

That’s because the modern-mined chert “hasn’t been weathered and washed by the river for many years,” Upchurch said. The colors depend on the minerals in the rocks.

According to a 1921 Tampa Tribune article announcing the completion of the Hyde Park home, it was the “only edifice in Tampa or elsewhere as far as can be ascertained that is comprised of that material. … The bungalow is a work of art.”

The developer, former Tampa City Council member H.P. Kennedy, acquired “sufficient stone” near his country home on Harney Road due to the “recent high waters,” the article says.

When the high waters receded, Dawson said, a large quantity of rocks that had been just under the sand were likely exposed. “Over the years, as I have driven along Columbus Avenue, I have always been intrigued by the church and often wondered where the builder was able to compile so much of this unusual building material.”

Kennedy also allowed the church to dredge rocks near his home for it building. It was designed to mimic British churches from the Middle Ages.

“No known deposit of this kind of rock in any quantity is said to exist anywhere else in the state,” the Tampa Tribune wrote when the church opened in 1923.

That was likely untrue, Upchurch said. Back then, there was plenty of chert in Tampa’s waters and along its streams and coastlines. He guessed that no one else dared use it for construction due to the skill it must have taken to collect enough and then use chert fragments as building materials.

Over the years, most of the local chert in the water has been destroyed by dredging and development, Upchurch said. Some probably remains in places in the Hillsborough River, but “I’m quite confident that it would be impossible to get permits to dredge the river because of environmental concerns. … Dredging would release too much sand, silt and other unwanted sediment constituents into the river.”

Not to worry, Mari said. She doesn’t expect to need more due to her confidence that the restoration will make sure the stones remain on the home for decades to come. “We’re going to clean it up and bring it back to life.”