Chinese Bronze Age dagger

adrian · 9th August 2012, 12:30 PM

A friend of mine owns this dagger, is was straight when he obtained it & over the years it has bowed quite badly. I examined it & explained that one side is corroding badly & that side is expanding & causing the bend.
He wishes to stabilise it (assuming the damage cannot now be reversed) what is the best treatment to do this? Coat it with wax?
Any advise gratefully received. Adrian

laEspadaAncha · 9th August 2012, 07:33 PM

Adrian,

I would advise your friend not to bother attempting to fix, reverse, or restore anything, as IMHO there is nothing worth restoring.

At present, I have in my possession about a dozen bronze artifacts, half of which are Bronze Age pieces. Two of the bronze artifacts are early ritual vessels from China (one Shang Dynasty, onr T'ang Dynasty) and four more are edged weapons.

Furthermore, while I cannot attest to having held a period-original Chinese Bronze Age sword, I have had the chance to see several exmaples in curatorial collections, and to see the corrosion process is parallel to ritual vessels of the same period.

Unfortunately, with regards to your friend's sword, I see several severe 'red flags' that would have resulted in a 'pass' should I have encountered it myself at auction.

Nevermind the fact that I have never once seen a bronze artifact that 'bent' like that over time. I am not a metalurgist and would be interested to hear from one about this rather bizarre claimed result of oxidation, on bronze or otherwise, though as I understand the corrosion process as it occurs on both bronze and steel, an 'expansion' shouldn't happen (aside from possible delamination).

I found three severe concerns, each enumerated in the below photo.

First, no. 1 (shown up close in the insert) shows a clear 'ladder' artifact in one of the cut grooves that is a clear indication of a drill having been used to create this particular channel. Not only is the technique incorrect for the period, but the regularly-spaced intervals indicates the use of an electric drill, and thus modern manufacture. That would be enough for me to walk right there.

Second, no. 2 shows the fitment of stone to metal is crude compared to what one would expect from period work. Nevermind distortion from the 'bend' of the blade; there is simply too much variance in the tolerance between the two materials in any given section for it to be period-original work.

Lastly, the presentation of crackling of the epidermal layer of the encrustation (no. 3) is bizarre to say the least, and if - and that's a big "if" - it is a natural by-product of the corrosion process, it is a statistical outlier, something that in and of itself would raise concern IMO, and in conjunction with all the other red flags that present on this piece, makes me inclined to say with near certitude this is a knock-off of recent manufacture.

Sorry to be the bearer of bad news, but this field of collecting is nothing if not a learning experience for all of us...

Regards,

Chris

.

Multumesc · 10th August 2012, 12:16 PM

A dive in vinegar 9 degrees a few days, wipe with a plastic brush, washing with distilled water, mineral oil lubrication.

fernando · 10th August 2012, 03:01 PM

Quite a comprehensive input Chris

.
This why i am awfully scared to buy bronze age artifacts.
I have had my own sour experience already

fearn · 10th August 2012, 05:41 PM

I'd be careful with the vinegar. My experience with my replica bronze sword is that it cleans quite quickly and produces spots if you aren't careful.

I'd also point out that in EUROPE (I don't know about China), ancient swords were sometimes "killed" by bending them or folding them into unusable loops.

That said, if you're going to buy a reproduction instead of a genuine relic, you might as well buy something from [DELETED] or a similar artist, and find out what they looked like when they were new. [DELETED] work is gorgeous, although it's not, strictly speaking, ethnographic.

Best,

F

Jim McDougall · 10th August 2012, 07:52 PM

This item truly is an interesting piece, and most of all bewildering in being posted in the European forum

usually its the other way around! In any case, it is great to learn more on these Chinese bronze age interpretations.

Chris, what an informative and beautifully written description which perfectly itemizes the details in recognizing items which are being produced as antiquities in comparison to the genuine artifacts. Thank you so much for providing this data!

All the best,
Jim

9th August 2012, 12:30 PM	#1
adrian Member Join Date: Mar 2012 Posts: 125	Chinese Bronze Age dagger A friend of mine owns this dagger, is was straight when he obtained it & over the years it has bowed quite badly. I examined it & explained that one side is corroding badly & that side is expanding & causing the bend. He wishes to stabilise it (assuming the damage cannot now be reversed) what is the best treatment to do this? Coat it with wax? Any advise gratefully received. Adrian Attached Images

9th August 2012, 07:33 PM	#2
laEspadaAncha Member Join Date: Aug 2006 Posts: 608	Adrian, I would advise your friend not to bother attempting to fix, reverse, or restore anything, as IMHO there is nothing worth restoring. At present, I have in my possession about a dozen bronze artifacts, half of which are Bronze Age pieces. Two of the bronze artifacts are early ritual vessels from China (one Shang Dynasty, onr T'ang Dynasty) and four more are edged weapons. Furthermore, while I cannot attest to having held a period-original Chinese Bronze Age sword, I have had the chance to see several exmaples in curatorial collections, and to see the corrosion process is parallel to ritual vessels of the same period. Unfortunately, with regards to your friend's sword, I see several severe 'red flags' that would have resulted in a 'pass' should I have encountered it myself at auction. Nevermind the fact that I have never once seen a bronze artifact that 'bent' like that over time. I am not a metalurgist and would be interested to hear from one about this rather bizarre claimed result of oxidation, on bronze or otherwise, though as I understand the corrosion process as it occurs on both bronze and steel, an 'expansion' shouldn't happen (aside from possible delamination). I found three severe concerns, each enumerated in the below photo. First, no. 1 (shown up close in the insert) shows a clear 'ladder' artifact in one of the cut grooves that is a clear indication of a drill having been used to create this particular channel. Not only is the technique incorrect for the period, but the regularly-spaced intervals indicates the use of an electric drill, and thus modern manufacture. That would be enough for me to walk right there. Second, no. 2 shows the fitment of stone to metal is crude compared to what one would expect from period work. Nevermind distortion from the 'bend' of the blade; there is simply too much variance in the tolerance between the two materials in any given section for it to be period-original work. Lastly, the presentation of crackling of the epidermal layer of the encrustation (no. 3) is bizarre to say the least, and if - and that's a big "if" - it is a natural by-product of the corrosion process, it is a statistical outlier, something that in and of itself would raise concern IMO, and in conjunction with all the other red flags that present on this piece, makes me inclined to say with near certitude this is a knock-off of recent manufacture. Sorry to be the bearer of bad news, but this field of collecting is nothing if not a learning experience for all of us... Regards, Chris . Attached Images Last edited by laEspadaAncha; 9th August 2012 at 09:26 PM.

10th August 2012, 05:41 PM	#5
fearn Member Join Date: Dec 2004 Posts: 1,247	I'd be careful with the vinegar. My experience with my replica bronze sword is that it cleans quite quickly and produces spots if you aren't careful. I'd also point out that in EUROPE (I don't know about China), ancient swords were sometimes "killed" by bending them or folding them into unusable loops. That said, if you're going to buy a reproduction instead of a genuine relic, you might as well buy something from [DELETED] or a similar artist, and find out what they looked like when they were new. [DELETED] work is gorgeous, although it's not, strictly speaking, ethnographic. Best, F Last edited by David; 15th August 2012 at 03:24 PM. Reason: NO COMMERCIAL LINKS!!!!

10th August 2012, 12:16 PM	#3
Multumesc Member Join Date: Feb 2012 Location: Romania Posts: 203	A dive in vinegar 9 degrees a few days, wipe with a plastic brush, washing with distilled water, mineral oil lubrication.

10th August 2012, 03:01 PM	#4
fernando (deceased) Join Date: Dec 2004 Location: Portugal Posts: 9,694	Quite a comprehensive input Chris . This why i am awfully scared to buy bronze age artifacts. I have had my own sour experience already

10th August 2012, 07:52 PM	#6
Jim McDougall Arms Historian Join Date: Dec 2004 Location: Route 66 Posts: 9,944	This item truly is an interesting piece, and most of all bewildering in being posted in the European forum usually its the other way around! In any case, it is great to learn more on these Chinese bronze age interpretations. Chris, what an informative and beautifully written description which perfectly itemizes the details in recognizing items which are being produced as antiquities in comparison to the genuine artifacts. Thank you so much for providing this data! All the best, Jim