Japanese Type 4 Ceramic Grenade 1944

[Brian Wolfe]

Hello Everyone,

Here is what I think is an interesting type of ordnance; the Japanese Type 4 Grenade, which is made of ceramic. It measures about 77mm in diameter.

In mid to late 1944 Japan was running short of vital war materials and with the American Military machine on the horizon, as it were, the Japanese were faced with the prospect of an allied invasion of the home islands. With iron in short supply the ceramics industry was pressed into service to make these grenades. I've read that these were supplied to the Japanese forces defending Iwo Jima and Okniawa, however, I do not know that they were ever used in any quality, if at all.

The hollow ball was filled with explosives and a blasting cap inserted into the top. This had a fuse with an abrasive striker ignition system. This in turn was covered with a rubber cap to keep the ignition system and explosives dry. It is rare to find these with the rubber piece intact or even pertially in place. The Type 4 was made in great qualities and the style and colour varies from manufacturer to manufacturer. A simple device and if used in qualitiy would have caused many casualties,had the allies invaded the mainland islands of Japan.

I have read that these are being produced in Mexico for the tourist trade. I'm more than a little sceptical regarding this as I can't imagine many tourists going to Mexico and purchasing a Japanese grenade. It could be true, I don't really know, anything can happen. Another factor, in my mind, against the Mexican story is that these are not all that expensive to begin with; so why copy them?

This one is from a dealer in Japan and I am confident that it is authentic.

Regards

Brian

[Brian Wolfe]

This is a view of the top. You can see how the rubber cap would have been secured easily. I have read that a throwing cord would have been secured to this top section as well to increase the distance of the thrown grenade.

[Brian Wolfe]

The last photo shows the unglazed bottom. The grenade was also glazed on the inside but showing that in a photograph is beyond the capabilities of my camera. Apparently there was nothing placed inside to act as projectiles, rather the thick ceramic shell provided the shrapnel; that and the usual concussion were intended to cause the injuries and or death of the enemy.

Thanks for taking a look at one of the newer additions to my collection.

Regards

Brian

[Hugh]

Remarkable! I've never heard of it. I wonder how well the frag pattern would work.

Hugh

[Mervyn Mitton]

Like Hugh, I must admit that I have never heard of a ceramic grenade - Japanese or, otherwise. They would have tested them before issue , so, they must have been effective - in the end a lump of metal or , hardened clay is going to be just as dangerous.

I agree with you about Mexico - why would they make copies of something that is quite rare - if anyone were do this, surely it would be the Japanese ? An unusual subject matter, Brian - a history of grenades would make a good post if someone had the time.....