What Is Stone Wash?

How is stone wash done?

Stone wash is done by tumbling finished denim garments, wet, in a large industrial washer with pumice stones until the stones have rubbed away part of the surface colour. A US patent filed in 1987 and assigned to Ecolab (granted 1989) describes stones of about 1 to 10 inches (roughly 2.5 to 25 cm), joined during the wash by smaller pumice particles broken off by the abrasion.

The fade works because of how denim is dyed. In classic denim, a cotton twill, the warp yarns are dyed with indigo and the weft is left white. The indigo sits mainly on the outside of each warp yarn, which textile researchers call ring dyeing. As the pumice scrapes dye off the yarn surface, the paler core of the yarn shows through.

After the wash, pumice fragments caught in the garments have to be removed by hand. The Ecolab patent calls this step de-rocking.

Stone-enzyme washing

Pumice is also used together with cellulase, an enzyme that breaks down surface cellulose. Researchers call this stone-enzyme washing, and a 2016 study in the Journal of Textile and Apparel, Technology and Management describes it as a finish typically used by the denim garment washing industry. Washing with enzymes and few or no stones is a separate finish, enzyme wash.

Who invented stone washing?

No single inventor is agreed: published accounts credit different people and companies, with dates ranging from the 1960s to the early 1980s.

• France, 1967 and 1981. The Encyclopædia Universalis article on jeans, by Pascale Gorguet Ballesteros, says François Girbaud developed a way of wearing cloth by rubbing it with pumice, “le stonewash”, in 1967. It says the Toulouse brand Liberto industrialised the process in 1981.
• 1960s, and Lee in 1982. The National Library of Scotland’s 1980s collection says stonewashed denim had been around since the 1960s, linking it to surfers who liked faded, soft jeans; it says their denim was bleached with chlorine or sunlight. It names no inventor, and dates Lee’s large-scale use of stone washing to 1982.
• Edwin, 1980s. The European website of the jeans company Edwin says the company invented stone washing in the 1980s.

These accounts cannot all be right about who came first. They also differ in kind: one is an encyclopaedia, one a library collection, and one a company describing its own history, which is not independent evidence. The question remains open.

What does stone washing do to denim?

Stone washing makes denim paler and softer, and in a 2016 study of stone-enzyme washing it also made the cloth weaker, more so as the amount of pumice rose.

• Colour. The Ecolab patent describes localised lighter areas from abrasion and similar lightening along the seams. In the 2016 study, pumice combined with cellulase removed up to 60% of the colour.
• Hand. The patent says pumice softens the fabric and leaves a fuzzy surface. In the 2016 study, untreated denim was stiffer and harder than stone-enzyme-washed denim.
• Strength. The same study found that durability depended on the amount of pumice. Acid cellulase with pumice at 70% of the garment weight caused the largest tensile strength loss, 34.9%. The authors named 30% pumice with 2% cellulase as the optimised washing condition.
• Absorbency. The study also found that stone-enzyme washing increased water absorption.

How is stone wash different from acid wash and enzyme wash?

Stone wash fades denim with plain pumice, acid wash adds bleach to the stones, and enzyme wash relies on cellulase with fewer stones or none.

Oxidative bleaching agents, with or without stones, are another route to a faded look; a fade done mainly with bleach is a bleach wash. Stone wash gives an overall worn look and is one of the finishes behind distressed denim, alongside localised effects such as whiskering. Denim that skips washing altogether is sold as raw denim.

How do you tell a good stone wash from a poor one?

Check three things: where the fade sits, how much strength the abrasion has cost, and whether the pumice was cleared out afterwards.

• Look at the seams and panels. Stone washing lightens the seams and leaves lighter abraded areas, with the pale core of the indigo warp showing through. Turn a leg inside out: the reverse shows the white weft, which is usually left undyed.
• Weigh softness against wear. Paleness and softness come from abrasion. In a 2016 study of stone-enzyme washing, strength loss rose with the amount of pumice, reaching 34.9% with acid cellulase at the heaviest load (70% of garment weight).
• Empty the pockets. Pumice fragments have to be picked out by hand after the wash, and the Ecolab patent says they tend to collect in pockets, creases and folds. Grit in the pocket bags or hem folds means that step missed some, and shows stones were used.

Red flags

• Sand-like grit in pockets or along hems
• Pumice grit in creases and folds as well as pockets, where the Ecolab patent says fragments tend to collect

Is stone washing sustainable?

Stone washing has documented environmental and operating drawbacks, many of them caused by the pumice.

• The Ecolab patent says abraded pumice can clog machine drainage, drains and municipal sewer lines and damage sewage processing equipment. It adds that the stones can damage washer motors, transport mechanisms and drums.
• A 2018 study in Fashion and Textiles names difficulty removing residual pumice, equipment damage and clogged drainage as major drawbacks of the technique.
• A study by Naveed and Zahid in Pigment & Resin Technology (2026) says traditional stone-enzyme washing needs significant amounts of pumice, raising concerns about water wastage, pollution and fabric damage. In their trials, a neutral cellulase wash cut pumice use from 12 kg to 1 kg, more than 91%, while keeping up to 85% of the fabric’s tensile strength. That is the result of one study, not an industry figure.

Replacing the stones altogether is an old idea: the Ecolab patent itself proposed a stone-free method that uses cellulase instead of pumice.