The Shichirin is a traditional Japanese charcoal cooking-grill made of diatomaceous earth (also termed ‘diatomite’ and in Japanese known as Keisodo). It is a special natural soil and is said to be the accumulated remains from a volcano sunk into the ocean or lake (a mixture of plankton, vegetation and volcanic ash). After a lapse of more than 20,000 years, a special natural soil is formed, and this Keisodo is the source material of Shichirin. This special soil substance has many air holes compared to other soils or clay, and when heated, its unique structure will sustain the heat at a high point inside the Shichirin, in addition to its fireproof features. Also the Shichirin will create certain ultra-infrared heat waves when used as a cooker. Also, a joint use of Shichirin & Sumi (natural hardwood charcoal) for cooking will create an additive amount of this special heat because Sumi has similar characteristics with the Keisodo used in making a Shichirin. Therefore, the cooked results will capture the real flavor of food and cook evenly, rendering the results juicy and tender. When broiling foods directly on the grill, alkalized ashes will help neutralize protein acids and other undesirable acid substances, delivering to you the pristine & delectable flavor possible in your cooked foods. The Shichirin was a part of every Japanese home’s outdoor kitchen and was the most universally used cooking device primarily because of its portable feature. This all-purpose cooking device has more than a 200-300 year history in Japan and was used in every corner of the nation. Everyone had a Shichirin whether or not they had a Kamado. Currently, Shichirins now in revival as a gourmet cooker in Japan even though gas, electric and butane grills are now more available. High-end Japanese style restaurants offer self-service cooking at the table with versions of Shichirin. The Japanese believe that cooking with a combination of Shichirin and Sumi is more health-promoting because of above mentioned features. They swear also that the results are tastier. Traditionally, the most expensive Shichirin are hand carved out of solid blocks of Keisodo. There is only one company making Shichirin with this way now.