Tea break – December 10th, 2016

Let’s take a talk about how ‘Shirasaya’ is good to keep the blade in good condition.

In Japan, many antique swords are remaining since Kamakura period (AD1185~) or forged even before.
Swords were cared with regard for long ages as a family’s treasure.
By the way, when you take a look at our website, you may find the blade in wood case (Shirasaya), or decorative outfittings (Koshirae).

Many customers ask us for those Koshirae ‘is these original?’.
Our answer is ‘No’ in most cases, unless the blade was forged after Edo period (Shinto, Shinshinto, Gunto or modern ages).
Before Edo period, Koshirae were usually made from lacquered woods, bamboo and leather.
Or with Samegawa (rayskin), silk or hemp for handle, those were not so decorative such like as you see in our fittings page or in film or anime. Koshirae were expendable utility at those ages.
Most of materials won’t last for hundreds of years except for parts made from some metals, but the blade made from forged iron only kept the condition for over several centuries.

One more reason it is difficult to find ‘original’ Koshirae is, every blades are polished or cut shorten in necessary during the history many times and the blade decreases slightly bit by bit by polish done over the ages. Size of the fittings becomes unsuitable some day.
But if you ask us ‘Is this Koshirae made for the blade to fit?’, we can give you the answer ‘Yes’.
Koshirae were repaired or remade with necessary in each periods.

Tsuba, Fuchi-kashira and Menuki becomes decorative around after Azuchi-Momoyama period (1573~) and becomes most luxury at peaceful ages under the rule of Edo shogunate. So most fittings sold in our shop were crafted at Edo period.

We can find original Koshirae crafted at Edo period, but even though, handle made from silk or hemp would be deteriorated related on the ages and restoration would be necessary in future.

The blade keep good condition with appropriate treatment.
But during long history in Japan, swords were prohibited several times by ruler at the age.
Swords were storaged somewhere with no care for long time while those were prohibited but many swords are still remaining.

Secret of the ancient blades still keeping good condition is also hidden on Shirasaya, the wood case made from Ho-no-ki (Magnolia obovata).
Wood of Shirasaya swell in high humidity or tightens at low and shut out unnecessary oxygen. So Shirasaya is effective to prevent rust (oxidize).

There for, we recommend the swords in wood Shirasaya, specially old one more then new.
Brand new Shirasaya still contain moisture of the woods so sometimes becomes too tighten under low humidity at some countries in overseas.
Old Shirasaya doesn’t become so tight, and good well to rest the blade. This is the reason Shirasaya is said ‘Yasume-Saya’ (sleepwear) in Japan.

And Shirasaya it self is also much easy to care then Koshirae.
Even if Shirasaya got dirty, it is rather easy to cleanup by scraping outer surface.

Or even when Saya got straight crack and started to split in half, it is possible to fix with glue made from glutinous rice to repair. Probably any common woodworking glues should work as well.
If there were gap on each side, you can adjust the shape by using warm water and settle using string and keep dry for while. You can also cleanup inside Saya doing same way.

Koshirae looks gorgeous, but we recommend blade in Shirasaya better for enjoying Hamon and work of Jigane in traditional way and also to keep the blade for long period with you.

Thank you for reading!


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