The history of ironware in Oshu City, Iwate Prefecture, begins when Mr Fujiwara Oshu prospered in Hiraizumi (around 1090). Kiyohira Fujiwara, the king of Hiraizumi, was the owner of Toyota, Esashiku, which is located in the east of present-day Oshu City. Then, we called in a foundry craftsman from Gangshu (present-day Shiga Prefecture) to take root in the foundry industry, and then made the bells of Chusonji Temple manufactured. Hiraizumi was registered as a UNESCO World Heritage Site in 2011, and there is a casting group here as a local industry that follows the flow of its culture.

Oigen Foundry was called Oikawa Genjuro Foundry in the Meiji / Taisho era and was incorporated in 1947 to become Oigen Foundry Co., Ltd.

During the Oikawa Genjuro Foundry era, the route was to go up the Kitakami River to Sendai and go to Sanriku by making "Tsuba kettle" and "Juice pot" for cooking rice and "Kaiba tub" for livestock such as cows and horses. I also carried the "sardine pot" used for sardines. "Bath Teppo" for boiling the bath was also a daily necessity. At the time of the war, craftsmen were driven into the war and production stopped in the absence of iron materials, and the iron in the factory was provided.

However, after the war, pot making was revived and the production area was busy.

After the high economic growth, casting machines were introduced into the factory, and the era of bending over and continuing to make everything by hand is over, and thanks to the strength of ironware products utilizing designers, we survived the oil crisis. Exports overseas began in the 1965's via trading companies, and are distributed to the United States, Europe, Australia, etc. Recently, OIGEN has launched its marketing of iron kettles, iron pots, and castings, and has also started direct export.

Since the beginning of the Heisei era, new products such as iron pots and iron kettles developed in-house have been enhanced, and I think the market has changed from Nanbu Tekki to Oigen's ironware.

It was in 2003 that the "High-grade pot (patented)" appeared as a new product in Nanbu Tekki, which has a history of 900 years and was thought to have no evolution. As a result of reviewing the factory setup and delving into the skills of the craftsmen, the creation of beautiful castings is the foundation of the "high-quality pot."

Buildings and factories were severely damaged by the Great East Japan Earthquake on March 11, 2011, but Oigen Foundry, which has overcome many difficulties since its establishment, is now thanks to everyone's help and the efforts of its employees. I am also steadily facing the casting.




  • 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’; a 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.

  • The beautiful iron surface is proof of traditional

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

Sand particles from the mould 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 moulds to check the consistency. The sand is very sensitive to changes in temperature and humidity, and the best way to monitor it is by a skilled hand.

  1. Sprues

A sprue is a passage through which molten iron flows into the sand mould. 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.

  1. Iron

Everything from large pots to small saucers is 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-degree centigrade. 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

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 mould. 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

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 flavour 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’

’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 grey surface is so fine and smooth that even oil from your fingers will leave a mark. Freshly cast iron is grey in colour and susceptible to rust from moisture in the air. Most Nambu Tekki is coated to prevent rust, however, we have developed a technique of heating the surface to 900-degree centigrade; thereby changing the surface structure making it naturally resistant to rust.



How to use and care

  • How to start using and care for the iron pot

For those who get an iron pot for the first time

Be sure to oil the iron pan before use.

Similarly, for iron products-iron frying pans, confectionery utensils, and grill pans, perform the same oil levelling as iron pans.

Oil levelling and care of iron pot

  1. Wash the dust and stains on the iron skin with a scrubbing brush. Wipe off the water by gently tapping it with a cloth or cooking paper.
  2. Heat the whole pot over low to medium heat until it warms up to evaporate the water.
  3. Reduce the heat and add enough oil to cover the bottom of the pot. Add chopped leafy vegetables and fry so that the oil blends evenly into the pot skin.
  4. After frying for 2 to 3 minutes, turn off the heat and take out the vegetables. When the iron pan has cooled, lightly wash it with a scrubbing brush and you're done.

Handling after using the iron pan

  1. After using the iron pot, wash it with a natural scrubbing brush, brush, sasara, etc.

* Do not use cleansers or steel scrubbing brushes.

  1. After cleaning, wipe off the water and heat it appropriately to evaporate the water and cool it.

* If you are concerned about oil stains or odours, use an appropriate amount of unscented detergent.

* Please do not use the dishwasher.

For long-term use of the iron pot

  • Be careful not to overheat.
  • Don't leave the food in it.
  • Do not leave the iron pot wet.
  • Don't leave it alone, let's use it.
  • Store it in a well-ventilated place.


  • How to start using and care for the iron kettle

For those who get an iron kettle for the first time

An iron kettle is a tool for boiling water.

Please refrain from using it for anything other than a water heater.

Here are some tips on how to take good care of your iron kettle and grow it well.

How to start using the iron kettle

  1. Remove the lid and lightly rinse the inside of the iron kettle with water. (Do not rub with a sponge or scrubbing brush.)
  2. Add water for about 8 minutes in the iron kettle and bring to a boil.
  3. Discard the boiling water.
  4. Please use after repeating boiling water and throwing it away 2-3 times.

Handling after using the iron kettle

After boiling the water in the iron kettle, open all the remaining hot water, remove the lid, and dry the inside of the iron kettle with residual heat.

Place the removed lid on your back.

Remove the lid and heat for about 30 seconds. As soon as the water inside the iron kettle evaporates, stop heating.

When you are worried about rust inside the iron kettle

  1. Fill the iron kettle with water until the 8th minute.
  2. Put the sencha tea leaves in a soup stock pack, bring to a boil, and simmer for about 20 minutes after boiling. The colour of the hot water will be black.
  3. Do not take out the tea leaves, pour water and fill it to the extent that it does not overflow.
  4. Leave the water in the iron kettle for about half a day and discard the hot water.

* If you are still worried about the colour of the rust, repeat this process 2-3 times.

For long-term use of the iron kettle

  • Rinse lightly without rubbing.
  • Be careful not to overheat.
  • Do not leave hot or cold water in the iron kettle.
  • Don't leave it wet.
  • Don't leave it alone, let's use it.
  • Store the iron kettle in a well-ventilated place.


How to start using and care for Tetsukyusu


Tetsukyusu is a tool for making tea. It cannot be boiled.

Start using

  1. When you receive the iron kyusu, first remove the tea kyusu and lightly rinse the iron kyusu, lid and tea kyusu. Wash the inside of the iron kyusu with a soft sponge.
  2. After washing, gently wipe off the water with a dry cloth.

Tetsukyusu -Handling after use-

  1. Lightly wash the inside of the iron kyusu and the tea strainer with a sponge.

(Do not use detergents, cleansers, or steel scrubbing brushes.)

  1. Wipe the entire iron kyusu and remove the water.

Please note that the colour may transfer to the cloth when wiping.

* The back of the lid of the teapot is a part that is easily rusted by steam. After use, wipe off the moisture with a dry cloth and move the lid slightly or turn it over to let the moisture escape to prevent rust. The edge of the tea strainer that comes in contact with the lid is also prone to rust, so wipe it well and dry it.

For long-term use of Tetsukyusu

  • Don't leave it wet.
  • Store it in a well-ventilated place.