Mirum Sustainable Leather Alternative: A Future-Forward Material

Why Leather Alternatives Matter

The Mirum sustainable leather alternative is one of the materials being explored as fashion looks beyond animal-derived leather and fossil-fuel-based synthetics.

When it comes to animal-derived leather, there are many ethical and environmental consequences of production worth evolving beyond, even if the material is a co-product of the dairy and farming industries. Some of these consequences include the exploitation and slaughter of animals, deforestation and inefficient land use, biodiversity destruction, significant greenhouse gas emissions, tannery pollution and worker’s rights issues across the supply chain. On the other hand, synthetic leather is still a plastic product derived from fossil fuels, which extraction is the leading cause of the climate crisis, and the synthetic materials produced from them can’t naturally biodegrade, and takes up to a 1000 years to break down, emitting the toxic cocktail into landfill.

While there are plenty of plant-based leather alternatives materials out there being explored and used, some of these are only partly plant-based and still blended with synthetics, which makes the material no longer fully biodegradable.

Update (2026): Natural Fiber Welding, the company behind MIRUM, has ceased trading. This article remains available as an archive of the material innovation and its place in the development of lower-impact alternatives. While MIRUM is no longer being commercially developed, it remains an important example of how the fashion industry has explored plastic-free, bio-based alternatives to conventional leather.

What Is MIRUM?

MIRUM is a new and innovative leather-like material that is entirely free from both animal and plastic inputs. This new material is certified to be made of 100% bio-content through the USDA’s biopreferred program and only uses natural blends that ensure recyclability at the end of the product’s lifespan, whether it is as a bag, shoe, belt or car seat. Similarly to how Piñatex uses plant leaves rather than the fruit itself, MIRUM uses plant matter and ‘upcycled’ agricultural products.

Depending on what the company who’s buying MIRUM wants to use this material for and the type of texture, feel, colour and thickness wanted, MIRUM will be made accordingly with slightly different inputs. So the truth about this material is that it is hard to define what it is made of as this aspect is always changing but we are optimistic that it is efficient and renewable.

At the time of its development, a growing number of brands experimented with the Mirum sustainable leather alternative, including companies producing bags, footwear and accessories. The examples below reflect the material's early commercial adoption and are included here as part of its historical development.

For example, a bag made by Melina Bucher features supple black MIRUM, and is made from a blend of Forest Stewardship Certified natural rubber, natural colourants like charcoal from pine, natural fillers like clays, plant-based oils and waxes.

AllBirds’ new plant-based leather sneaker features a blend of MIRUM that also includes agricultural byproducts such as rice hulls and citrus peels. This sneaker has been officially launched on the 13th September 2022 with the name of “Plant Pacer Sneaker”.

For the sneaker brand Camper, Natural Fibre Welding, the company developing MIRUM, delivered a plant-based material made from a blend of natural materials like coconut husk, rice hull, rubber, and cork, making the product not just sustainable but also circular.

Australian Certified B Corp Bellroy was one of the first brands to release products made with MIRUM, including wallets, bags, phone cases and laptop sleeves, demonstrating how the material could be applied across a range of accessories.

Italian Certified B Corp Modher also experimented with MIRUM, creating a small crossbody bag as part of its exploration of lower-impact alternatives to conventional leather.

MIRUM's Carbon Footprint

MIRUM’s first carbon footprint assessment found that producing one square metre of the material results in as little as 0.84kg of carbon equivalent emissions (CO2e), with the higher end of the estimate equating to 2.1kg of CO2e. That’s equal to roughly the same amount of greenhouse gases required to wash and dry one load of laundry! When we talk about sustainability, the climate impact of a material is extremely important and these results have huge implications for the future of fashion. Although MIRUM is no longer in commercial development following the closure of Natural Fiber Welding, its reported environmental performance and material innovation represented an important milestone in the search for lower-impact leather alternatives. It demonstrated that plastic-free, bio-based materials could challenge conventional assumptions about what leather alternatives might look like, and its legacy continues to influence conversations around circular material innovation.

What Can You Do?

Look beyond broad claims such as "vegan leather" and check whether a material contains plastic, how it is produced, and what happens at the end of its life. While MIRUM itself is no longer commercially available, the questions it raised about transparency, bio-based materials and circular design remain just as relevant. Supporting brands that openly disclose their materials and invest in credible lower-impact innovation helps drive the industry in the right direction.

[info sourced on voguebusiness.com, sustainably-chic.com, camper.com, vegconomist.com, davidson.weizmann.ac.il and mirum.naturalfiberwelding.com

Featured image byIrene Kredenets on Unsplash

Image 1 byKelly Sikkema on Unsplash

Image 2 byLOGAN WEAVER | @LGNWVR on Unsplash

Image 3 by Agung hendri on Unsplash]