Made together with Japanese brand Tajimi Custom Tiles, the sculptures have a cylindrical body with added square and rectangular tiles and are sat on sand-covered ceramic tiles.
"It's almost an architecture done in ceramic; structures made from ceramic extrusions and wood that are connected together," Ronan Bouroullec told Dezeen.
The pieces were made using a type of clay extrusion normally used for tile production and come in pale pastel hues that make them look "almost like candy".
They were designed to showcase the potential of ceramics by using the company's tile-production machines to create items that weren't products.
"We made objects like this to see tiles from a different perspective and show the technical possibilities," Glaettli told Dezeen.
The Bouroullec brothers began the project with Tajimi Custom Tiles, which makes custom-designed tiles for architectural projects, during the coronavirus lockdown.
The company is located in Tajimi, an area in Japan that has a tradition of ceramic-making that goes back more than 1,300 years, but as a result of the pandemic, the designers could not travel to work with the tile makers in person.
Instead, they had to rely on samples in different hues and shapes sent over from Japan, including the striking tubes made from extruded clay.
"We did everything in cardboard in Paris," Ronan Bouroullec said. "We did tonnes of projects; this one is the result of two years of work."
The shapes in the collection, which is named Sosei – a word suggested by one of the brothers' Japanese studio assistants, which means assembly – got their forms both from the designers playing around with different combinations of tiles and from the process of making the clay itself.
"The time to dry was very short so there was a lot of movement in the piece, which made the shape move a bit," Bouroullec said. "I think that's part of the beauty of it."
The collaboration between Tajimi and Ronan and Erwan Bouroullec came about after Ronan Bouroullec saw Tajimi Custom Tiles' 2020 exhibition featuring designs by Max Lamb and Kwangho Lee, which are also on display at Milan design week and were originally shown in Tokyo.
"I knew [the Bouroullec brothers] well and was following their work, especially Ronan's artworks and ceramic objects," Glaettli said.
"As the original exhibition was made during Covid, people couldn't see it in person, but images of it spread online and Ronan sent me a message to congratulate me. And I said, well actually, do you want to join?"
For Ronan Bouroullec, creating the sculptures was a chance to explore his passion for ceramics but also to draw attention to craft skills that are on their way to disappear.
"We know that this world is fragile everywhere, we can see it – the craftsmen disappear, and we need to be careful of that," he said.
"It's the role of the designer to fight to continue to search and feed this technique with new approaches and new ways, it's important," he added. "It's because of that that this technique, this way of working and these people will survive."
Milan design week takes place from 6 to 12 June 2022 in Milan, Italy. See our Milan design week 2022 guide on Dezeen Events Guide for information about the many other exhibitions, installations and talks taking place throughout the week.