Radioactive Tosogu?

[vajo]

Just for fun, I took some measurements of my collection using two different Geiger counters. I noticed that the old *tsuba* actually registered slightly elevated radiation levels. One Tsuba from the Muromachi period, featuring gold inlay, really started clicking away. Everything is still well within the safe range — but where does it come from?

 

[ROKUJURO]

Did you purchase it from a FUKUSHIMA or HIROSHIMA located collector? 

[The Blacksmith]

Other than the above possibilty, any mercury used in the various treatments and decoration when the tsuba was decorated may perhaps be very slightly radioactive.

[Scogg]

Are they more, or less radioactive than a banana? 

For context: It's a little ongoing scientific joke to compare latent radioactivity to a banana; because banana's have a slightly elevated level of radiation compared to other everyday objects/foods.
https://en.wikipedia.org/wiki/Banana_equivalent_dose

[John C]

Two Geiger counters?

Also, did any of the tsuba develop super powers?

 

All kidding aside, could be from natural uranium found in many types of rocks and minerals, even those used to make tsuba. Or, the tsuba could have been exposed to high levels of radon gas for a period of time.

 

John C.

[Kantaro]

same here but without gold inlay

[ROKUJURO]

54 minutes ago, John C said:

Two Geiger counters?....

John,

if I remember correctly, John Wayne always had two.

[vajo]

I have two, because one of them is already nearly 20 years old, and I don't know how long the Geiger tubes last. Now I have a new one as well. However, the readings from the old one are still accurate.
 

[vajo]

52 minutes ago, Kantaro said:

same here but without gold inlay

 

Thanks Kantaro 

I measure between 0.20µSv and 0.26µSv on that tsuba
In the room, I have 0.11µSv – 0.15µSv normal. 
 

 

[BjornLundin]

Doesnt "new" iron contain a bit of radiation due to the present atomic age and old iron (item) pre atomic age does not? 

[Rawa]

31 minutes ago, BjornLundin said:

Doesnt "new" iron contain a bit of radiation due to the present atomic age and old iron (item) pre atomic age does not? 

It's more about atomic explosions and air. Air is irradiated and used to produce steel.

That's why metal from pre 1945 ship wreckage is called low-background steel and is used for example to build computed tomography. 

BTW steel made in atomic period is used to build Geiger's counter casing? I guess Yes, so it by itself can be doing interferences :D

I guess that irradiation from Fukushima was more dangerous and that there are some counters at airports to prevent sending atomic waste overseas.

I thought about this when I was watching documents from Fukushima, all were abandoned as was in moment of catastrophe. Tasty JDM cars were left, all manga in shops etc.

Edited May 3 by Rawa

[Spartancrest]

From Hiroshima -   the lights do flicker a bit in the room! 

[vajo]

Has anyone other than Kantaro taken measurements? I don't think this has anything to do with atomic bombs or power plant accidents.
Moreover, the Tsuba do not date from the 2011 timeframe.
 

[Hokke]

3 hours ago, vajo said:

Has anyone other than Kantaro taken measurements? I don't think this has anything to do with atomic bombs or power plant accidents.
Moreover, the Tsuba do not date from the 2011 timeframe.
 

My guess would be they have come into contact with other items that are mildly irradiated over the years. That's the real the problem with radiation, it cant be seen so we have no idea when we are in its presence unless its being measured. Anyone remember fiesta ware? Colored plates made in the 30's where uranium was used to give its color containing about 4,5g in each plate. Im no scientist, so im not sure how radiation can be transmitted between objects, but I believe if someone were wiping something down that was irritated and used the same cloth for tsuba, there would be transmission to some degree.

[Rawa]

1 hour ago, Hokke said:

My guess would be they have come into contact with other items that are mildly irradiated over the years. That's the real the problem with radiation, it cant be seen so we have no idea when we are in its presence unless its being measured. Anyone remember fiesta ware? Colored plates made in the 30's where uranium was used to give its color containing about 4,5g in each plate. Im no scientist, so im not sure how radiation can be transmitted between objects, but I believe if someone were wiping something down that was irritated and used the same cloth for tsuba, there would be transmission to some degree.

Luminous watch hands, dials originally with radium were done „by hand”. Girls doing paint job liked to use their lips.

 

 

Edited May 4 by Rawa

[Rawa]

1 minute ago, Rawa said:

Luminous watch hands originally with radium were done „by hand”. Girls doing paint job liked to use their lips.

 

 

Radiation is like damaging „light” it goes in every direction damaging stability in matter it hits.

Edited May 4 by Rawa

[vajo]

This has all nothing to do with the initial thema.

I see Godzilla coming.

[vajo]

Who has a geiger counter? 

Edited May 4 by vajo

[Robert S]

Some context around the prevalence of radioactive elements :  I had my well tested last year, and they found Uranium in the water.  Had me a bit worried until I got some context : The level of Uranium was an order of magnitude less than that found in your average bottled water!  After that, I relaxed.  Given that older Japanese iron may have been made from iron sands, it would not be at all surprising to find some radioactive elements in the mix... not to mention small amounts of gold :-).

[John C]

1 hour ago, Robert S said:

not to mention small amounts of gold :-).

As a metal detectorist, that's exactly what I think about when I read about black sand!

 

John C.