Chalk & ?

[Spartancrest]

I was just studying some tsuba in the Ashmolean Museum [not from the A.H. Church collection] and found two "odd" entries. These two guards are described as having ategane made of chalk - really? Has anyone ever seen ategane/ume made of such soft and not very long lasting material? Has the museum's curator mistaken bone or shell for chalk? Or is it misidentified "white" metal?  A new one on me!

https://www.ashmolea...em/ash-object-367336        https://www.ashmolea...em/ash-object-366401

       

 

EA1956.2059

Mokkō-shaped tsuba with dragons, clouds, and aoi, or wild ginger, leaves. Iron, with openwork decoration, inlaid with silver and gold; hitsu ana holes plugged with chalk.
83 mm x 77mm

Presented by Sir Herbert Ingram, 1956.

 

 

EA1978.392

Round tsuba with design of Daruma floating on a bamboo leaf. Iron, inlaid with copper and gold; copper sekigane (soft metal lining) added to tang-hole; hitsu ana holes plugged with chalk.
signed:  to..mitsu with Kakikan
83 mm x 77 mm 

Presented by D. Newman, 1978.

 

[Matsunoki]

Don’t think it’s “white metal” judging by the way it has overspilled onto the figure of Daruma. I wonder if it’s white paint onto a normal metal base? Dunno, bizarre.

[Geraint]

Well, museums are funny places and we sometimes give their descriptions more credit than we should simply because their code of reference is much different to our collector code.

 

My guess would be lead ategane corroded to a white soft surface, compare here, https://www.research...-1910_fig2_276594062

 

All the best.

[Matsunoki]

12 minutes ago, Geraint said:

My guess would be lead ategane corroded to a white soft surface, compare

Yep, reckon you’ve nailed it Geraint,  I’ve got many old percussion cap balls in pistol cases that have gone exactly like that….covered in white powder oxides. 

[Bugyotsuji]

Tell the musum staff to lick them and see if the white stuff tastes sweet. 

[Spartancrest]

31 minutes ago, Geraint said:

lead ategane corroded to a white soft surface

That would explain any 'chalky' rub off if they were handling the piece - they drew the wrong conclusion. I hope they didn't taste test it! 

Or maybe they did - that would explain the wrong conclusion, a consequence to the loss of a few brain cells from poisoning 

 

Hey Piers I was just writing about a taste test 

[rkg]

That would be the arsenic leaching out of the lead

Best,

rkg

(Richard George)

[Spartancrest]

3 hours ago, rkg said:

That would be the arsenic leaching out of the lead

[Brian]

From a financial point of view, Liking Tsuba can also be hazardous to your (financial) health

[Spartancrest]

I 'C' what you did there! 

[ROKUJURO]

So called 'lead white' is a basic lead hydroxy carbonate, 2 PbCO3 · Pb(OH)2. No arsenic involved. In former times, it was used as pigment in painting and in pottery.

[Steves87]

It is exceptionally uniform and contrasting, I can't decide if it was intentional or purely just time induced?

[ROKUJURO]

It is not really rare and you can find it also on other items than just TSUBA. It develops slowly under special conditions (exposure to acids and carbon dioxide in a warm environment).