To commemorate 10 years of fossil research on Kangaroo Island, located in southern Australia, Kangaroo Island Brewery has launched a first-of-its-kind ale with a particularly unique trait: it is filtered through 514 million-year-old fossils. “We just thought for this one, why not let the millions of years of shale rock speak for itself and see what comes through?” the brewery’s Mike Holden said. “The beer has a unique flavor to it, but it is not something that is off-putting or maybe something that people will not even recognize.”

In case you’re unfamiliar with beer brewing, breweries filter for clarity. The process involves mesh that catch particles that cloud the brew. It’s like straining pasta. Holden and his team are using prehistoric shale to filter their craft beer. We haven’t tasted it, so whether that idea is interesting or disgusting is completely up to you.

Kangaroo Island has long been a digging ground for palaentologists. This year marks a decade of fossil hunting for professor John Paterson, who, with his colleague Diego Garcia-Bellido, have collected roughly 6,000 specimens from the space for the South Australian Museum. “[The fossils] are from a very special time in Earth’s history called the Cambrian…when we started to see the first marine animals appearing on Earth,” he said. “We get very fine preservation, even down to finding muscle tissues and the lenses within the eyes of some of these strange arthropod creatures.

Given the fact that the number of local craft brewing businesses has increased from 30 to 379 in the last decade, Kangaroo Island Brewery’s "shale ale” feels like nothing more than a marketing gimmick, akin to the spikes in hard sodas this year and hard ciders a few years ago. It’s a strategy breweries have to adopt in order to keep afloat: recreate one of the oldest tipples for increasingly persnickety consumers. Independent Brewers Association executive officer Chris McNamara told ABC News that Australian producers are frantically finding their niche through seductive backstories. “Small brewers are an innovative mob, so they are always looking for a different spin to put on their beer,” he said.

Stateside, overcrowding is just as much a concern. More than 5,000 breweries are competing in a limited market where, surprisingly, much of the growth remains propelled by local brands opposed to corporate beer houses like Anheuser Busch. And because craft beer cannot be traded across state lines due to U.S. commerce laws, craft brews remain a niche market.

Still, the crowded space is pushing out a growing number of craft brewers. “I’ve heard speculation from a couple of retailers that perhaps the fact that there were too many choices has in fact turned customers away from craft,” said the chairman of Boston Beer Company, which produces Sam Adams in a Fortune interview. Nearly 100 craft brewers closed its doors last year, an increase from 78 in 2015 and 75 in 2014. And it seems like things will continue this way for some time. “The era of 18 percent growth rate is probably over,” Bart Watson, chief economist of the Brewers Association has said. “The industry is a maturing industry. Having those growth rates in an industry of this size is impossible going forward.”