Blue Cast: Hand Made Stone’s Beyza Baykan on Easing Denim’s Pumice Problem
Blue Cast is a podcast series from the TENCEL™ Denim team. Each episode features a conversation with a special guest from within the industry or the fringes of the denim community. The following is a recap of episode 502.
Denim customers continue to seek out authentic vintage faded looks, but the process to create this aesthetic has traditionally left behind environmental hazards.
Stonewashing is just what it sounds like: Pumice stones are placed into washing machines to abrade denim during wet finishing. While this achieves the desired looks, the stones have their downsides. For one, they absorb chemicals during the wash and degrade, creating a sludge that must be disposed of. Each kilogram of stones results in 3 kilograms of sludge. Multiply that by the average 100 tons of pumice stones used by denim laundries per month, and the impact is huge, explained Beyza Baykan, founder of Hand Made Stone, in the most recent episode of our Blue Cast podcast.
“It’s an insane amount of sludge being created globally,” said Beyza. “So people wanted to somehow stop this without giving up the aesthetics that pumice gives.”
Family firm Hand Made Stone has created an alternative to pumice that saves water and energy and cuts the sludge, achieving a green EIM score. Back in 2012, denim veteran Yavuz Baykan (Beyza’s father) began researching and developing an option that would create the desired look without the environmental impact of pumice. He initially took sludge and chemically separated it to extract and clean pumice dust, which he then joined together with ZDHC-approved binding. However, this sludge recycling process uses significant chemicals and energy, and the resulting stones would be different based on varied factory methods. The current version of the stones uses pumice dust from mining operations that would otherwise go to waste, achieving more uniformity and saving on footprint.
It took five years to create a stone with the right specifications. First, Yavuz wanted the stone to last longer than pumice stones, which degrade in the first wash. In comparison, HMS’s stones only degrade 2-3 percent per wash. The stones also had to be rough and porous to create friction with the fabric. As another benefit, HMS stones are hydrophobic because of the binder, meaning they do not absorb chemicals or water in the laundry. Additionally, while pumice leaves behind dust that must be rinsed off, HMS’s products do not require this additional rinse, saving hundreds of liters of water. Unlike sludge, any HMS particles left behind after the wash can be treated in an effluent treatment plant.
Three years after the final design was created, a patent was finalized in 2020. The same year, Beyza—who had been working as a consultant at the World Bank—returned home to Türkiye during the pandemic lockdowns. She spent time with her father and saw the potential in his pumice alternative. Using the extra time she gained from the early Covid-era shutdowns, she started what was initially her “side hustle” with help from a grant for young female entrepreneurs. The company quickly gained interest from industry players like Candiani Denim and took off.
After finishing up school in Los Angeles, Beyza eventually left the World Bank to focus on Hand Made Stone. Her father became the chief technology officer, managing production and R&D, and her mother Ayse Baykan retired from the health sector and joined the firm, overseeing accounting and exports.
HMS has gathered support from major brands, including Mud Jeans, who in turn asked factories to switch to its stones. The remaining challenge is to get the industry to consider the overall cost benefit of HMS—including energy and water savings—compared to the higher up-front cost. “[HMS is] an innovation, it comes with so many more advantages,” said Beyza. “At the end, it is cost beneficial, but you need to be able to use it in a large scale to see those [benefits].”
The company has also made a direct-to-consumer play with a pen-shaped stone that consumers and independent designers can use to customize denim with patterns or whiskering.
Expanding beyond its initial B2B product, the firm also created HMS Light, which is made for lighter weight fabrics like TENCEL™. Looking ahead, HMS plans to debut three new stones in 2024, with current R&D focused on a stone that works better for black sulfur-dyed materials, one for recycled fabrics and stones in different shapes.
“The thing about HMS that our customers like the most is that it’s customizable,” Beyza said. “It’s one of the biggest benefits of being a boutique family company, because we can actually customize stones for different types of fabrics.”
Listen to the episode here.