Undulating in a Utah Museum of Fine Arts gallery, thousands of glimmering casts seem to float throughout the space. For his large-scale installation “Stone on Boundary,” Japanese artist Yasuaki Onishi has suspended 5,000 copper foils that he molded over river rocks in both Osaka and Salt Lake City.

Begun in the artist’s studio in Osaka—a city where Japanese copper has been refined for export for around two centuries—the installation then traveled to the museum, which sits less than an hour’s drive from the world’s largest operational open-pit copper mine. Using an element found in both places and mirroring waterways or rippling topography, Onishi connects two seemingly unrelated locations through a common material and industry.

The artist has long been interested in how objects interact with their surroundings, especially the relationship between “positive” and “negative” space. This spurred a deep dive into molding techniques and unique uses of materials, which allow him to explore themes revolving around margins, voids, boundaries, and volume. For the Salt Lake City installation, he considers the relationship between earth, the landscape, and extraction.

“The copper foil created by Onishi presents such absence and presence through molding, suggesting that to recognize things, it is essential not only to know the surface but also to richly engage the imagination—and that even with imagination, one cannot see everything,” the museum says.

For “Stone on Boundary,” the thin metal molds create disc- and cup-like shapes that suspend along a wire framework, which reflects the Wasatch and Oquirrh Mountains around Salt Lake City. The installation also marks the artist’s largest to date, spanning 12 x 22 x 14 meters.

Find more on Onishi’s website and Instagram.