How One German Button Maker Searched the Rivers of the American Midwest for the Shells That Could Make Him a Fortune

John Boepple settled in Muscatine, Iowa, where he produced pearl buttons made from freshwater mussel shells. His innovations brought economic prosperity to the town—and disaster to the local mussel populations

Ellen Wexler | Writer and Special Projects Editor

June 25, 2026

How an ebonyshell mussel becomes a button © Historic Muscatine, Inc. / The National Pearl Button Museum – Muscatine, Iowa

This story begins with a button maker and a box of mussel shells.

In the mid-1800s, the box in question somehow found its way to John Boepple’s button shop in Ottensen, Germany. Some sources claim the shells were harvested from the Illinois River and sent to Germany by a man who wanted an assessment of their manufacturing value. Others link them to the Mississippi. In many accounts, Boepple knew only that they’d arrived from a location 200 miles west of Chicago.

What he also knew—and what his competitors didn’t understand—was how valuable they were. Based on their density and luster, these mussel shells could be used to make high-quality pearl buttons. And pearl buttons could be used to make a fortune.

John Boepple circa 1891 The National Pearl Button Museum – Muscatine, Iowa

Boepple immigrated to the United States in the late 1880s, resolving to search for more of these freshwater mussels. At the time, several pearl-button factories were operating in the Midwest, but they were importing ocean shells rather than harvesting mussels from nearby rivers. As the story goes, the button maker was bathing in the Sangamon River when he cut his foot on something sharp.

“Upon examination of the cause, I found the bottom of the river covered with mussel shells,” he later recalled. “At last I found what I had been looking for.” These shells, however, were too thin. After searching for other mussel beds in nearby towns, he ultimately settled in Muscatine, Iowa, where he made his first buttons in 1891.

By 1905, Muscatine had dozens of factories and produced 1.5 billion buttons per year. “That’s kind of an abstract number until you do the math,” says Dustin Joy, director of the National Pearl Button Museum in Muscatine. If you piled up 1.5 billion buttons, each about one-eighth of an inch thick, “that’s a stack 2,900 miles high.”

At its peak, the button industry in Muscatine produced 1.5 billion buttons per year. The National Pearl Button Museum – Muscatine, Iowa

In just a few years, the town doubled in size, becoming a central hub for button production. It also devastated the local mussel population. “It was a boon for this town, because it created a lot of jobs, provided a lot of prosperity,” says Joy. “But it was an environmental catastrophe.”

How pearl buttons were made

Muscatine’s button boom is now featured in an exhibition at the Smithsonian’s National Museum of Natural History (NMNH). Titled “From These Lands,” the show commemorates America’s 250th birthday by showcasing more than 600 items, representing all 50 states. Mussel shells and pearl buttons from Iowa, in various stages of production, are on display.

Mussels, drill bits and mother-of-pearl buttons. The mussels were collected in 1907 from Dubuque and Muscatine Counties in Iowa, and the buttons were created in the early 20th century. National Museum of Natural History

For Boepple, buttons were the family business. At his shop in Germany, he had learned to craft them out of wood, shell, horn and bone. But pearl buttons brought in the biggest profits. When a German tariff put him out of business, Boepple became one of the nearly 1.5 million Germans who immigrated to America in the 1880s. “They each brought their own skills,” Joy says. “Mr. Boepple was a button maker.”

Boepple had little money and spoke poor English. But after securing a financial partner, he established a small plant in Muscatine, which became the foundation of a lucrative industry. Locals noticed his strategy—profiting from a free resource found in the river—and tried to copy it.

Mussels “essentially paved the bottom of the river in certain parts,” says John Pfeiffer, a research zoologist and curator of bivalves at NMNH’s department of invertebrate zoology. “The factories were positioned right on top of these really large mussel beds, because it made it that much more convenient to collect them.”

The cutting room of U.S. Button Company circa 1915 The National Pearl Button Museum – Muscatine, Iowa

Pearl buttons became a thriving industry, supported by clammers who used a variety of techniques to harvest mussels. Sometimes they would wade into the river, feeling along the bottom with their feet. When the water froze in the winter, they’d collect mussels through holes in the ice. One of the most efficient methods involved crowfoot hooks, which workers would drag along the bottom of the river. When the hooks touched the inside of a shell, the mussels would reflexively clamp down.

Clammers searched for mussels with particular qualities. The shells needed to be thick enough to make a button—and, ideally, large enough to make many buttons. Workers then removed the meat and drilled out circular discs (called “blanks”) from each specimen. After grinding down and polishing the blanks, workers used machines to drill holes. Another group of workers, usually young women, sorted the buttons by color.

“One might come from a washboard mussel out of the Mississippi; the next one might come out of an ebonyshell mussel from the Ohio River,” Joy says. “All these buttons varied. That’s aesthetically very pleasing, but from the point of view of a buyer who wants them to make 10,000 coats or shirts or whatever, they would like them all to be the same.”

Women working at Hawkeye Button Company circa 1910 The National Pearl Button Museum – Muscatine, Iowa

The decline of the pearl button

The pearl button industry fundamentally changed the character of Muscatine. Even today, “if you meet somebody whose family is from here,” Joy says, “it’s almost certain that somebody in their family worked in the button industry.”

The industry’s influence spread across the Midwest. Joy remembers walking along the Mississippi River in Keithsburg, Illinois, where his grandparents lived, and finding mussel shells riddled with holes. After factories and blanking shops punched out button-size circles, turning the shells into something resembling thick pieces of Swiss cheese, they often dumped them back into the rivers.

Clammers searched for shells that were large enough to make several buttons. © Historic Muscatine, Inc. / The National Pearl Button Museum – Muscatine, Iowa

These discarded shells, which can still be found, illustrate the scale of the mussel harvest—and why it ended. At first, clammers had harvested near the factories, but as they depleted their supply, they ventured farther away. Freshwater mussel populations plummeted.

“Supply-and-demand was going to end the pearl button industry at some point,” Joy says. “It was just a heedless use of this natural resource. That seems to be a lesson we have to learn over and over in this country.”

Freshwater mussels are vulnerable. To survive past the larvae stage, they must become parasites that attach themselves to fish. Once they transform into juveniles, they disconnect and find new homes in the sediment. “As you can imagine,” Pfeiffer says, “if the fish populations are declining, that oftentimes has an indirect effect on mussel abundance.” They also grow slowly, requiring years to develop shells large enough to satisfy clammers.

The decline of pearl buttons also coincided with the rise of consumer plastics. Plastic buttons weren’t higher quality, but they were much easier to produce. “It was cheaper, required less labor and, of course, [was] not subject to the reproduction of a species of river life,” says Joy. “Any company that didn’t start to switch to plastic didn’t survive.”

Quick facts: The rise of plastics

• During World War II, when natural resources were scarce, synthetic plastics served as a cheap alternative.
• Production of plastics in the United States increased by 300 percent during the war, according to the Science History Institute.
• When the war ended, plastics became common in consumer products, such as Tupperware containers and nylon stockings.

In Muscatine, large factories started closing between the 1920s and 1940s. But even without the pearl button industry, freshwater mussels weren’t out of danger. Around the same time, the U.S. Army Corps of Engineers deepened the rivers and constructed a system of dams, destroying the habitats of mussels that had evolved to live in shallower waters. Increasingly polluted waters also took a toll.

“They are kind of like the canary in the coal mine of freshwater ecosystems,” Pfeiffer says. “They are filtering in everything that gets put into the water, and they’re doing it for long periods of time—often multiple decades.”

Freshwater mussel conservation

While the button boom devastated freshwater mussels, it also triggered early efforts to preserve them. As clammers harvested mussels faster than the bivalves could reproduce, business owners started to worry. “In kind of an ironic way,” Pfeiffer says, “the pearl button industry started freshwater mussel conservation.”

In 1908, Congress established the Fairport Biological Station in Iowa so that experts could study freshwater mussels and try to reintroduce them into the Mississippi River. Two years later, Boepple himself took a position at the station, where he contributed new harvesting techniques and documented the size and properties of mussel beds.

Pimpleback mussel shells © Historic Muscatine, Inc. / The National Pearl Button Museum – Muscatine, Iowa

Despite his innovations, the button maker never became a successful businessman. “He ordered unnecessary equipment and chemicals to confuse potential competitors,” according to the Biographical Dictionary of Iowa. “He remained attached to his ideals as an Old World craftsman, opposed automation and struggled with English.” When he died in 1912, he had few assets to his name.

Boepple’s story came full circle in 1911, when he came across a heelsplitter in an Indiana river. These mussel species have shells with sharp edges that stick out of the ground, and people tend to step on them. “Legend has it that John Boepple walked out into the stream, stepped on a heelsplitter, cut his foot and allegedly died from an infection,” Pfeiffer says. “So the mussels got their revenge, allegedly.”

Today, freshwater mussels are still endangered, and several species are thought to be extinct. But state and federal regulations protect many species, and some have even returned to the Mississippi River. Although Muscatine’s last pearl buttons were manufactured in the 1960s, perhaps their little-known story can be instructive.

“I think all history is valuable,” Joy says. “By learning what people did in the past, both right and wrong, we learn to make better decisions in the future.”

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