Materials for the Beads and Frames of Abacus ......
Materials for the Beads
The most suitable materials for abacus beads are ones that fulfill the following four conditions:
1. Need to be heavy
2. Will not split
3. Will not shrink
4. Availability (needs to be in plentiful supply)
There are very few types of wood that fulfill the above criteria. Due to the nature of the abacus, the beads must be able to move fast and accurately. Therefore, they must not be too heavy, nor be too light. The most suitable woods for beads are birch, box tree and sawtooth oak.
Materials for the Frames
The most suitable materials for abacus frames are ones that fulfill the following four conditions:
1. Dark in color (to make a clear contrast with the beads, so that the user can concentrate better)
2. Need to be heavy
3. Will not shrink
4. Will absorb the vibration of bead movement
|Birch||Grown in Iwate Prefecture. The Japanese scientific name is "ono ore kanba" meaning "axe breaking birch" and it is very hard. It is skin color, which is easy on the eyes and plentifully available. This is probably the most commonly used material|
|Grown in the People's Republic of China and Hiroshima Prefecture in Japan. The bright yellow color makes it easier to see in dimly lit places. The wood produces a slight stickiness that makes the movement of the beads heavy due to friction between the beads and the bamboo rods. This unique feeling of weight cannot be produced from any other wood and is loved by many abacus users. Especially, the Bingo box tree (designated as a precious natural product by the Japanese government) is said to be the very best amongst box trees, renowned for its weight and beautiful pattern.|
Grown in Kagoshima Prefecture. It has a chocolate color and is heavier than birch and box tree. There are many sawtooth oak lovers in the Kyushu region.
|Grown in Tanzania and Kenya. It has a black color and is heavy. When placed in water, it sinks. It is not suitable for fast calculations, however, this is used as a frame material. It was introduced to Japan after World War II and it is only used for the abacus|
|Plum||Grown in Japan. It is slightly lighter than birch. This was used a lot in the Edo (1603 - 1868) and the Meiji (1868 -1912) eras.|
|Red wood||Grown in Thailand. It has a dark red color and is heavy. It is rare, therefore, very valuable.|
|Rosewood||Grown around the equator in many parts of the world. It is used for making wooden crafts.|
|Blue Ebony||Grown in Thailand. It is very rare and valuable. Used as a frame material for top quality products. This wood started to be used during the Taisho ear (1912 - 1926). Due to its shrinkable nature, it requires more than 20 years of drying, making this wood very rare. It has a mysterious green black color that is suitable for high quality abacuses. However, this wood is no longer seen, even in Thailand.|
|Laminated Wood||Used as a frame material. Layers of thinly sliced wood are compressed and processed. It is hard to twist or break.|