For the last 50 years wetsuits have been made from neoprene, a petroleum-based rubber filled with nitrogen to create an insulating barrier against cold water. Neoprene has about a 70 percent water impermeability, which makes a two-to-three-millimeter-thick suit comfortable to wear in 60-degree-or-higher water. However, in colder water, neoprene suits cannot provide sufficient insulation unless they are up to five or even seven millimeters thick. Thick neoprene suits restrain swimming performance in the water, forcing surfers to choose between being either cold and flexible or warm and immobile.
In the early 1970s, Yamamoto Corporation of Japan developed an alternative called geoprene. Geoprene is an organic rubber constructed out of 99.7 percent limestone (primarily made up of the ancient shells of marine organisms). It offers up to 98 percent water impermeability at half the thickness and lasts twice as long as its neoprene counterpart (which can degrade after six months as nitrogen leaches from the suit).
"People were shocked to try on a suit that was so warm, flexible, styled right, and that would last longer, perform better, and was environmentally friendly," says John Campbell, founding partner of Matuse Wetsuits, the first U.S. wetsuit manufacturer to use high amounts of geoprene in its suits. In 2005, Matuse expanded its line of geoprene suits and, as a result, opened up new possibilities in cold-water surfing. "I have a year-and-half-old Matuse I surf in when the water is 30 degrees and it’s minus 5 out," says Yassine Ouhilal, a surf photographer who lives and surfs in Nova Scotia. "I could never have done this in a neoprene suit.