Hada

Since Japanese Swords are made from folded steel, the fold lines, or weld lines, are visible. These fold lines, called Hada, vary depending on the way the blade was folded, the number of times folded and the direction of the fold. There are many variations of the hada pattern and only the standard examples are presented here. All of these can have small and large variations, stretched variations and mixed variations. The references will show and define more patterns.

Masame

The grain is fairly straight and not crossing. There can be waves and can look like a topographic  map.

Itame

This commonly is described as wood grain pattern. There are swirls and straighter areas but they are not connected or regular.

Konuka

This pattern often called rice grain and is similar to Nashiji hada. Hizen blades are known for this hada.

Mokume

This grain pattern looks like burls or connected swirling pattern. They usually look like knots and can be stretched out. O-Mokume is in large patterns. Ko-Mokume is in small paterns.

Ayasugi

This is a regular pattern of curved lines with waves in it. The lines do not cross, but are very different than Masame. Ayasugi is often seen in Gassan and Naminohira school blades.

Muji

This gain pattern is difficult to identify and can't really be seen. The grain is there but so small that its not seen with standard polishing techniques.

Nashiji

Called pear skin, this style results from the steel being folder a few more times than the standard Mokume.