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Why Is Urushi So Expensive and Have a Short Shelf Life?

Updated: Oct 7

The True Value of Urushi: Why This Priceless Natural Lacquer Deserves Your Respect

kijomi urushi, japanese lacquer
Premium ki urushi is Japan-grown urushi with the highest content of urushiol. Also known as kijomi urushi.

Kintsugi, the ancient Japanese art of repairing broken pottery with gold and lacquer, has gained immense popularity worldwide. But as more people explore this craft, they encounter a vital question: Why is urushi, the traditional Japanese lacquer, so expensive—and why does it have such a short shelf life?


Many who compare authentic kintsugi materials to commercial kits find urushi far pricier than synthetic adhesives like epoxy. On top of that, natural ki-urushi only lasts about a year. Let’s dive into why this organic material is so valuable and why it requires proper care, unlike faux alternatives.


Why Is Urushi So Expensive?

Japan urushi tapping

The cost of urushi comes down to the labor-intensive process of harvesting it. Each urushi tree takes approximately 10 years to mature, requiring meticulous care throughout its life. And what is the yield after all that time? A mere 200ml of sap—the equivalent of a small latte.

Urushi sap is collected drop by drop, by skilled artisans who extract tiny amounts during brief harvesting windows each season. After just five months of harvesting, the tree is cut down, and the process starts again with a new tree. This sustainable yet time-consuming cycle makes urushi not only rare but also precious—much like fine wine or hand-crafted cheese.

Moreover, artisans trained in urushi cultivation are becoming increasingly rare. With fewer foresters tending to these trees, the scarcity of high-quality urushi continues to grow.


Why Does Urushi Have a Short Shelf Life?


Unlike synthetic adhesives, urushi is a living, organic material. Think of it as dairy or fermented products like cheese or yogurt. Its key component is a natural enzyme named lacasse that drives the lacquer's ability to harden through a process called polymerization. Lacasse enzyme must stay alive and healthy for urushi to work its magic, but it is sensitive to the environment.

If improperly stored or exposed to extreme conditions—the enzyme can degrade, rendering the lacquer ineffective. It’s the same reason fresh produce or yogurt spoils over time. Urushi is carefully refined by artisans who balance its water and oil content or bind minerals to create a range of colors. But in all cases, the enzyme must remain active, making proper storage essential for maintaining its longevity.


The difference between ki urushi (raw urushi) and color urushi is, ki urushi is in its original form, refinery may aged or adjust the water content to create different ki urushi products. While color urushi went through various low-heat processes to bind mineral colors into ki-urushi. The heat also changes the water content (water and urushiol ratio) and viscosity, but care is taken to retain the active enzymes.


ki red black urushi japanese lacquer

Storing Ki Urushi: Treating It Like a Living Material


To preserve urushi’s quality, it must be stored properly. In many cases, urushi “breathes” inside its container, fermenting and expanding like a living organism. If kept in a warmer environment, you may even notice it oozing out or inflating the tube. On the other hand, storing urushi in a cooler environment like a refrigerator can help slow down its activity, prolonging its shelf life, for up to 1 to 2 years.

Professional artisans typically store urushi in wooden or paper buckets, with a sheet of paper pressed onto the surface to allow for natural breathing. However, extremes like freezing or overheating will destroy the active enzymes, drastically changing the lacquer’s performance.

Experienced users of urushi have the ability to adjust their practices, take advantage of, or manipulate the environmental conditions to make urushi performs in different manners.


storing urushi, shelf life of urushi

Typical advise is, try to use urushi within 3-6 months of purchase. Store in the fridge for hibernation if the urushi is not used frequently. If you have urushi that has been stored for a long time, check for bad odor which indicates spoilage and mold. If it doesn't smell bad, mix in a small amount of fresh urushi and let the new natural active enzymes reactivate the old batch. If uncertain, you can always test old ki urushi for adhesiveness or its hardening ability on a piece of wood or pottery before using it on an actual project.


Sometimes, if you have not used the ki-urushi and left it in room temperature for long awhile, you will noticed the tube inflated. It means the urushi is active and fermenting. Use this as a reminder to use your urushi and start a new kintsugi project! If continue to left unattended, the urushi will try expand and push open the tube.



Understanding the Limitations of Faux Kintsugi Kits and Workshops


In today’s growing kintsugi market, there are many options for those interested in learning the craft. However, some kintsugi kits use synthetic alternatives like epoxy, and certain workshops focus more on the philosophy and aesthetics of kintsugi rather than delving into the deeper knowledge of urushi. While these offerings can introduce people to the art, they may not fully capture the true essence of traditional kintsugi.


Workshops often focus on the “wabi-sabi” aesthetic and serene imagery of buddhist temples and forests. Some focus on showing step-by-step instruction and formulas to mix various bases, but fail to communicate the most critical point: No urushi, no real kintsugi. Without an understanding of the material's properties, even after completing workshops and courses, many students frequently face issues like mold, improper drying, wrinkling, or failing repairs.


Urushi requires respect, patience, and a lifetime of learning. It’s not enough to follow a step-by-step guide to mix the base and bond broken pottery. You need to know the craft’s foundation—urushi itself. With the right fundamental knowledge and invest time to experiment and practice, over time, anyone can master kintsugi.


Join Us in December to Learn More About Urushi


Urushi is far more than just an adhesive or a finish. It’s an organic material with deep cultural roots and immense value. If you’re ready to truly understand urushi and its connection to nature, we invite you to join us for a forestry tour in December, where you can witness firsthand the cultivation of this precious resource and learn from artisans who dedicate their lives to mastering its craft.


Discover the beauty and wisdom of urushi by immersing yourself in its origins—There is still time to reserve your spot for the 2024 urushi forestry experience. Other wise, plan to join us in 2025!


urushi and kintsugi workshop in japan




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