OIGEN quality is
about more than
just functionality
and design.


Through regular use, these iron instruments crafted by hand in this harsh climate become invaluable lifelong partners, backed by the OIGEN quality assurance.

Making our own tools


Here in Mizusawa, Iwate Prefecture, cast-iron production has long been a part of life for the agro-industrial population. Throughout history, villagers made the tools they need by themselves in order to get by.

During the third president, Genjuro’s time, even large and complex cooking stoves called Kamado were made from cast-iron, using techniques that are no longer alive today.

Rice cookers and soup pots were also made out of necessity. During the harsh Tohoku winter, there was always a ‘Zogama’ pot of hot water hanging over the hearth.

Robust tools that stand the test of time. They may not have ornate decorations, but the simple form feels natural in your hand. OIGEN continues to manufacture tools that fit the lifestyle of the time.






Beautiful iron surface is
proof of traditional

Cast iron is made by pouring bright orange molten iron ore into a sand mold. Once the iron has cooled and hardened, the mold is broken to take the product out.

Sand particles from the mold are reflected in the surface of the iron. These minute sand marks are what determine the beauty of the surface. At OIGEN, we judge the quality of products by the beauty of these marks.

Iron and Sand,
techniques passed
down through
generations of artisans

OIGEN products are renowned for their beautiful surface. This is made possible by generations of refinement by skilled artisans.


1. Sand

Frequently throughout the day, artisans feel the sand used in molds to check the consistency. The sand is very sensitive to changes in temperature and humidity, and the best way to monitor it is by skilled hand.


2. Sprues

A sprue is the passage through which molten iron flows into the sand mold. These sprues are hidden from sight, and in order to design them correctly, one must have a thorough understanding of the properties of iron and sand. This skill is imperative to manufacturing the diverse range of products OIGEN is famous for.


3. Iron

Everything from large pots to small saucers are made using the same sand, with adjustments to the ore temperature for each item. Ore for large pots is poured in quickly at high temperature, and for small saucers, the temperature is dropped by around 200℃. Each of the many products has its own specific requirements. Through years of experience, artisans master all the minor adjustments required to create each product.

Naturally beautiful iron surface

Naturally beautiful iron surface

If the condition of the sand, sprues and ore is not just right, the iron surface can take on an unnatural rough or even shiny appearance, or form lines that resemble worms, putting the lifespan of the product at risk.
That is why at OIGEN we take pride in maintaining the highest precision through every step of the process, ensuring a final product that is sure to satisfy customers straight from the mold. Any part such as edges that need attention are finished carefully by hand, however the beautiful surface, which is the pride of OIGEN artisans, needs no finishing.

Grows with your care

Grows with your care

Lately you can pick up convenient pots, pans and electric kettles for cheap. However, many of these tend to wear out or break after a few years.
With a little care, ironware can be passed down through generations. Over time, oil coats the surface making it easier to use. This has been an essential element for passing on the flavor of family dishes in Japan.
We hope that you will choose cookware that will grow with you through time, to prepare food for the people you love. In this throwaway society, that is one thing we at OIGEN hold dear.

Thinking ahead to the next generation Revolutionary new technique ‘Naked Finish’

Thinking ahead to the
next generation
Revolutionary new technique
‘Naked Finish’

‘Naked’ refers to the state of being newly born. Achieved by OIGEN through deep knowledge of the properties of iron and sand, this technique using just iron and sand was developed for a sustainable future and patented in 2006. Like a newborn baby, the subtle gray surface is so fine and smooth that even oil from your fingers will leave a mark. Freshly cast iron is gray in color and susceptible to rust from moisture in the air. Most Nambu Tekki are coated to prevent rust, however we have developed a technique of heating the surface to 900℃, thereby changing the surface structure making it naturally resistant to rust.

Naked Finis
Naked Finis

Naked Finish surface

Ordinary Nambu Tekki surface

*Nambu Tekki are often thought of as being black due to the image of sukiyaki pans and kettles. The black color that is so synonymous with hard, strong iron is actually a coating used to protect the iron from rust. Traditionally, coatings were made from lacquer, however post WWII a similar coating derived from cashew nuts has become more common.

Oigen quality is founded on tradition passed down through generations of craftspeople, and is enhanced with continued innovation.
We will continue producing safe ironware from natural materials.

To product list

A selection of OIGEN-quality products