By Tyson Bottenus, Clean Regattas Director,
Sailors for the Sea

When we think of building boats and the materials possible to build boats, we think of wood, we think of plastic, we think of fiberglass and aluminum, but we don’t consider boats made from rock. They would sink, right?

But in 2015, a unique race called the Sailing The Arctic Race (STAR) was proposed to bring attention to a modern day environmental problem: the melting of the ice caps. The organizers of the STAR said in a press release, “We shouldn’t be able to do it, but because of climate change, we can.” Slated to begin in New York and end in Victoria, British Columbia, crews would race 7,700 miles through the Northwest Passage on a new class of high-performance boats called STAR 46s. What made the STAR class unique wasn’t their lines, or their design. It was the material the yachts were built from. Eschewing traditional carbon fiber, STAR 46 boats were created from “volcanic fiber.” As in, fiber, made from volcanic rock.

Proponents of volcanic fiber construction, nicknamed by some to be the “next generation of carbon fiber” claimed to offer several advantages over traditional carbon fiber, including additional strength without added weight, and a less-energy-intensive production.

Although the race folded before it ever began, the idea of using basalt (volcanic rock) as a material to build boats has not. From a boatbuilding perspective, made sense on paper. Compared to traditional fiberglass, basalt glass was touted as stronger, had a much higher UV resistance, was fireproof, acid-proof, as well as being abrasion and shock resistant. And from a sustainability perspective, volcanic fiber was touted as being more recyclable than traditional fiberglass. But how true are these claims?

Added Strength

When race organizers for the STAR were in the planning process of the race, a huge concern was the amount of ice racers would encounter as they circumnavigated the Southern Ocean.

“Hitting an iceberg or hitting a container has always been a concern to somebody,” says Richard Downs, President of the Landing School, a boatbuilding school in Arundel, Maine. “How strong is this and can I hit something with it? If you know the history of composites, Kevlar or aramid fiber were popular for impact performance. People would put one layer of Kevlar on their boat and say, ‘well now I’ve got a bulletproof boat.’ In reality they would need to put many layers of Kevlar in it before it became bulletproof.”

Downs, a Kiwi, is just as comfortable talking about iceberg-resistant boats as he is talking about kangaroo-resistant cars. “In Australia, cars have ‘roobars with the idea that you could hit a kangaroo and your car would be fine. But it still goes that if you have a ‘roobar and you drive it off a cliff, your car is still going to get damaged.” The same logic, he argues, applies to iceberg-resistant boats.

“The idea that you could add something like basalt fiber to your boat so you could hit an iceberg and make it unsinkable like the Titanic has been proven not to be true.”

Basalt-fiber, explains Downs, is stiffer than fiberglass. “But you don’t need to build your boat out of Kevlar or carbon to make it stronger, you could make your boat out of fiberglass, you’d just have to put more material down to have the same amount of strength.”

A Sustainable Alternative to Carbon Fiberglass

In addition to its strength and stiffness, addressing the “end-of-life” problem in boat manufacturing has become a hot-button issue and from an environmental standpoint, it makes sense. Traditional fiberglass is difficult and expensive to repurpose. Crushing and reusing fiberglass wind turbines creates hazardous dust and the market to buy used carbon fiber is small at best. Volcanic fiber, on the other hand, is completely recyclable and marks a shift in the boatbuilding industry away from plastic towards a more sustainable material.

The process for recycling basalt-fiber is similar to recycling fiberglass in Downs’ eyes. “The whole business of recycling finished composites is tricky because you have remove the resins. If you have a boat made from basalt fiber, who is going to recycle it?”

“I don’t see basalt fibers as being particularly recyclable.” It’s similar, he equates, to how we recycle our conventional plastics. “Currently, we put all our plastic at the end of the driveway to see it get recycled but instead see it gets shipped off to China where it gets incinerated. So, I haven’t seen anything to make the case that basalt fiber is anymore greener than any other composite we have.”

As it stands, there are two boatbuilders in Europe who have pledged commitments to building volcanic fiber boats in an effort to introduce a more “cradle-to-cradle” production in the boatbuilding industry. If they can overcome the difficulties inherent in recycling basalt-fiber there’s a chance that this could represent a distinct new era. Traditional fiberglass boats have been around since the late 1950s and carbon fiber boats have been the de facto since the 1980s.

Basalt fiber has been around since it was first patented in the 1920s. It originally was used for military applications in the Soviet Union and in the United States, and eventually spread into more industrial applications before the boatbuilders became interested in its applications.

In the marine market, says Downs, “people have been getting excited about it for ten to fifteen years, but I just haven’t seen it find much application.” From a materials perspective, volcanic fibers show significant improvement over traditional carbon fiber, and from an environmental perspective, many boatbuilders are interested in its promise of being 100% recyclable. For now however, the technology is still in its infancy but as more and more boats start making the shift, there’s reason to believe that we could see more and more “rock boats” plying the oceans. “There are advantages,” concludes Downs, “but if I wanted stiffness or strength, I’d use carbon.” ■

This Sailors for the Sea Ocean Watch essay is reprinted with permission. Special thanks to Amber Stronk MAS, Communications Manager at Sailors for the Sea powered by Oceana. To learn more and to join the race to restore ocean health, visit