Stockholm-based artist duo Bigert & Bergström has created a pink crystal-shaped sauna on a remediated industrial site in Skellefteå, northern Sweden.

Named Lithium Crystal Sauna, it is the first permanent structure completed for WasteLand Climate Action Park – a project transforming one of Västerbotten's most polluted industrial sites into public space.

After more than a century of pollution caused by toxic chemical emissions from pulp production, the Scharin industrial site underwent 17 years of extensive soil remediation work before being turned into a public park.

"Rather than erase the site's history, we wanted to build upon it," Bigert & Bergström told Dezeen. "Our ambition was to create a combination of a sculpture and a fully functional sauna."

Clad in pink titanium-coated mirrored stainless steel, the sauna has an asymmetrical faceted form made of approximately 280 prisms. The structure was designed digitally and cut with CNC machines and laser technology.

Designed to resemble an enlarged lithium crystal, it was intended to reference the mineral's role in battery technology and the transition to renewable energy.

"Lithium interested us because it has become an emblem of the green transition," the artists said.

"It is associated with batteries, electrification and a fossil-fuel-free future, but its extraction can also create serious environmental damage. That contradiction felt highly relevant in Skellefteå."

The structure leans backwards at an angle of four degrees, designed to appear as though it has emerged from the ground. It sits on a hexagonal wooden deck made from local heartwood pine.

According to Bigert & Bergström, its distinctive pink finish was created by evaporating titanium and condensing it onto the stainless steel in a vacuum chamber.

"The mirrored exterior reflects the river, forest and the returning vegetation, but also a landscape that has been profoundly altered by industry," the duo said.

Lithium Crystal Sauna is heated by a custom battery-operated heater. Filled with 260 kilograms of olivine stones inside a metal cage, it is clad in black flint sourced from the coast of Normandy.

"The heater was designed to operate using stored green electricity, including power supplied from standalone batteries or electric vehicles," Bigert & Bergström said.

"Although its energy system belongs to the future, the heater's form refers to humanity's oldest tool – a 2.5-million-year-old stone chopper."

In contrast to the mirrored exterior, the sauna's sculptural interior is formed from heat-resistant wood veneer over a spruce frame.

"When you enter the sauna, it's like stepping into a cave. It connects to the earliest period of human life, when we sought shelter in caves and began making fire to keep warm," the duo said.

With room for up to 12 people, the sauna is fitted with handmade alder benches arranged around the heater, while a glazed doorway frames views over the Skellefte River.

Local heartwood pine was used for the flooring, chosen for its naturally resin-rich composition, meaning it can withstand moisture and decay without chemical treatment.

"Crystal Sauna is a social and performative artwork: a place where people can gather without any of the usual social barriers and talk about changes taking place around them," said Bigert & Bergström

"We hope it will become a place that people feel belongs to them – not simply an artwork to look at, but somewhere to meet, pause and spend time together."

Other sauna projects recently featured on Dezeen include a dark and moody private sauna in New York by BoND and a sauna and tea room in Finland by Jaakko Torvinen supported by charred tree trunks.

The photography is by Pär Olofsson.