A Story of Four Swords: A Technical Evaluation of Counterfeit Bronzes (in Chinese)
14
085 /2012/ / 85-98 * Gordon Turner-Walker* Wang, Chu-ping X- (XRF) 4 4 2 2 2 (SEM) 4 X- Abstract Four “ancient” Chinese bronze swords were examined using low-power light microscopy and X-ray fluorescence analysis (XRF). All four of the swords were patinated and slightly corroded and they all appeared to have an inlayed paern in a white metal. Two of the swords were intact but two had broken handles allowing examination of the bulk metal as well as the patinated outer surfaces. ese swords were then compared with fragments of two archaeological bronze weapons of genuine antiquity. ese laer were examined metallographically using plain and polarized light, and scanning electron microscopy (SEM). e results indicated that the four “ancient” swords were modern counterfeits and that the “inlay” was not inlay at all but in fact had the same composition as the bulk metal the swords were cast from. Based on microscopic examination of the paern a suggested mechanism for the production of these swords is presented. Keywords: Chinese, Bronze Swords, Metallographic Analysis, XRF, SEM, Inlay, Fake A Story of Four Swords: A Technical Evaluation of Counterfeit Bronzes * [email protected]
Transcript of A Story of Four Swords: A Technical Evaluation of Counterfeit Bronzes (in Chinese)
085
/2012/ / 85-98
*Gordon Turner-Walker* Wang, Chu-ping
X- (XRF) 44 2
22
(SEM) 4
X-
AbstractFour “ancient” Chinese bronze swords were examined using low-power light microscopy and X-ray
fluorescence analysis (XRF). All four of the swords were patinated and slightly corroded and they all appeared to have an inlayed pattern in a white metal. Two of the swords were intact but two had broken handles allowing examination of the bulk metal as well as the patinated outer surfaces. These swords were then compared with fragments of two archaeological bronze weapons of genuine antiquity. These latter were examined metallographically using plain and polarized light, and scanning electron microscopy (SEM). The results indicated that the four “ancient” swords were modern counterfeits and that the “inlay” was not inlay at all but in fact had the same composition as the bulk metal the swords were cast from. Based on microscopic examination of the pattern a suggested mechanism for the production of these swords is presented.
Keywords: Chinese, Bronze Swords, Metallographic Analysis, XRF, SEM, Inlay, Fake
A Story of Four Swords: A Technical Evaluation of Counterfeit Bronzes
086
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
1.
90
()
90%
100%(Allen, 2001) eBay( )
90
(Allen, 2001) (GTW)
20074
( 1)
12
42
(Milburn, 2008)
(Milburn, 2008 1992)
2
2.2.1.
600 670477 500
3 ( 1 24) 3
Carps Tongue Sword2
43
12 3
4
3
2
087
/2012/ / 85-98
1
2
( 2)
(Cu2O)( 3A)
()
2( 3B)3
3( )
4 1 2
2
2.2.
1-4Seiko SEA 200 X-
1
2
3
4
1. Figure 1. �he four bronze swords examined.
1
2
3
4
088
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
088
4
1 22
(Buehler Epoxycure)
() Ultra 55
LE FE-SEMINCA
( )
3.1 X- (XRF)4
1 3( 47.25 0.77%
46 .02 0 .94% 45 .07 0 .87%47.69 0.82% )
A
B
3. 2
Figure 3. Fracture surface of Sword 2 showing red cupric oxide internal corrosion����. The original surface���marked with the white arrow. Mixed green and yellow external corrosion is indicated with the black arrows.
A
B
2. 1(A) 2(B)(B)
Figure 2. Comparison of the fracture surfaces of Sword 1 (A) and Sword 2 (B). Note the gas porosity (bubbles) in B and the band of red Cu2O on the interior surface.
A
B
A
B
089
/2012/ / 85-98
4. Figure 4. Copper and tin contents of the four swords examined.
090
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
090
(wt%) (wt%)
1 1 47.34 45.98 5.99 0.65 0.03 1 2 46.56 47.28 6.17 0.00 0.00 1 3 47.48 46.01 6.48 0.00 0.02 1 4 47.05 45.66 6.77 0.52 0.00 1 5 48.73 44.55 6.66 0 0.07 1 6 47.82 45.02 6.60 0.54 0.01 1 7 46.47 47.00 6.53 0.00 0.00 1 8 46.57 46.64 6.28 0.50 0.01
47.25 46.02 6.44 0.28 0.020.77 0.94 0.27 0.30 0.02
1 1 50.67 42.71 6.21 0.41 0.00 1 2 49.77 39.28 6.30 0.00 0.00 1 3 50.89 42.12 6.49 0.50 0.00
50.44 41.37 6.33 0.30 0.000.59 1.83 0.14 0.27 0.00
1 10.25 78.64 10.23 0.52 0.00 1 35.33 55.11 3.99 5.57 0.00 2 1 35.70 53.92 9.06 1.14 0.18 2 2 33.03 58.41 8.15 1.28 0.13 2 3 33.10 56.42 8.39 1.29 0.17 2 4 33.86 56.26 8.37 1.29 0.12 2 5 31.88 58.34 8.19 1.41 0.15 2 6 31.69 58.47 8.11 1.52 0.20
33.04 56.97 8.38 1.32 0.161.55 1.81 0.35 0.13 0.03
2 1 57.06 37.20 5.75 0.00 0.00 2 2 53.54 40.60 5.86 0.00 0.00 2 3 49.36 44.94 5.71 0.00 0.00
53.32 40.91 5.77 0.00 0.003.85 3.88 0.08 0.00 0.00
2 36.43 53.54 8.84 1.19 0.00 3 1 44.99 47.48 6.80 0.59 0.14 3 2 44.18 48.84 6.31 0.59 0.07 3 3 44.98 47.97 3.29 0.64 0.12 3 10 45.71 47.22 6.55 0.51 0.00 3 11 46.22 46.54 6.70 0.54 0.00 3 12 45.62 47.19 6.65 0.53 0.00 3 13 43.78 48.60 7.07 0.56 0.00
45.07 47.69 6.62 0.57 0.051.57 1.58 0.15 0.23 0.00
3 1 52.26 41.48 5.83 0.43 0.00 3 2 54.87 38.95 5.81 0.37 0.00 3 3 52.06 41.85 6.08 0.00 0.00
53.06 40.76 5.91 0.27 0.001.57 1.58 0.15 0.23 0.00
1. X- XRFTable 1. Results of XRF analyses for the four swords. Data shows compositions in weight percent for the patina, the
"inlay" and the bulk metal seen in the broken edges.
091
/2012/ / 85-98
4 1 26.77 60.80 8.77 1.77 0.18 4 2 25.99 63.26 8.47 1.67 0.19 4 3 26.71 63.14 8.23 1.70 0.22 4 4 27.14 63.00 8.29 1.56 0.00 4 5 26.86 63.64 7.82 1.68 0.00
26.69 62.77 8.32 1.68 0.120.43 1.13 0.35 0.08 0.11
4 1 50.24 43.85 5.91 0.00 0.00 4 2 40.84 51.94 6.12 1.10 0.00 4 3 50.51 43.22 5.66 0.61 0.00
47.20 46.34 5.90 0.57 0.005.51 4.86 0.23 0.55 0.00
4 33.43 58.37 6.90 1.31 0.00 1 1 50.02 43.64 5.79 0.55 0.00 1 2 50.44 42.70 6.32 0.53 0.00 1 3 51.27 42.07 6.12 0.54 0.00
50.58 42.80 6.08 0.54 0.000.64 0.79 0.27 0.01 0.00
2 1 53.26 40.03 6.28 0.44 0.00 2 2 47.38 46.34 5.81 0.46 0.00 2 3 52.96 39.55 7.17 0.32 0.00
51.20 41.97 6.42 0.41 0.003.31 3.79 0.69 0.08 0.00
2. EDXTable 2. Results of EDX analysis on the authentic archaeological bronze fragments.
(wt%) (wt%)
X50 28.21 5.34 46.40 5.99 5.61 2.78 0.00 0.30 0.59 3.72 0.37 0.25 0.44 X100 30.51 4.15 44.50 2.33 8.63 2.51 1.22 0.25 0.51 4.29 0.66 0.16 0.29 X200 28.71 4.17 44.80 4.33 9.21 2.49 0.84 0.41 0.57 3.25 0.84 0.24 0.13
1 30.65 4.81 47.06 3.24 5.35 2.89 0.17 0.39 0.58 3.78 0.37 0.17 0.53 2 28.46 5.54 48.32 0.85 5.70 3.11 1.98 0.32 0.59 3.88 0.44 0.25 0.57
29.31 4.80 46.22 3.35 6.90 2.75 0.84 0.33 0.57 3.78 0.54 0.21 0.391.18 0.64 1.59 1.95 1.86 0.26 0.81 0.07 0.03 0.37 0.21 0.05 0.18
1 24.54 8.08 52.27 6.55 0.28 2.55 0.00 0.18 1.13 3.22 0.40 0.38 0.432 24.28 8.13 53.75 3.47 0.42 2.78 1.14 0.31 1.18 3.28 0.31 0.44 0.50
24.41 8.11 53.01 5.01 0.35 2.67 0.57 0.25 1.16 3.25 0.36 0.41 0.470.18 0.04 1.05 2.18 0.10 0.16 0.81 0.09 0.04 0.04 0.06 0.04 0.052.83 75.25 16.67 3.18 0.28 0.57 0.38 0.72 0.00 0.00 0.00 0.00 0.122.57 73.47 17.67 2.62 0.27 0.97 0.60 0.73 0.44 0.19 0.04 0.23 0.202.70 74.36 17.17 2.90 0.28 0.77 0.49 0.73 0.22 0.10 0.02 0.12 0.160.18 1.26 0.71 0.40 0.01 0.28 0.16 0.01 0.31 0.13 0.03 0.16 0.060.97 84.72 10.05 1.18 0.37 0.37 0.66 0.79 0.18 0.23 0.09 0.19 0.211.81 65.10 25.89 3.10 0.30 1.31 0.29 0.68 0.40 0.27 0.00 0.20 0.66
- 1.94 67.32 26.04 0.00 0.25 1.37 1.38 0.76 0.11 0.14 0.00 0.05 0.64- 1.77 60.92 30.15 3.23 0.26 1.66 0.00 0.90 0.15 0.18 0.06 0.14 0.58
092
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
2 4 1 3( 33.04 1.55%
56 .97 1 .81% 26 .69 0 .43%62.77 1.13% )
47-53% 40-47%
4A-C 4A4B
4C 1 2 4C
1 2
1 6-9%
2
4
56
6
72
74% 7% 3%
( 3)
alpha( ) delta( )(Scott, 1991) 85% 10%
( 2)
( 8)65% 26%
67% 26%61% 30%
9
( 10)
2
2 ( 11)
(Scott, 1991)2
3. Table 3. Reported compositions for various Chinese
bronze weapons.Cu
(wt%)Sn
(wt%)Pb
(wt%)Lin et a. 1997 78.60 17.10 4.20Li 2007 83.15 13.26 1.01Lin et al. 1997 82.80 11.60 5.20Collins 1934 77.83 19.25 1.93Lin et al. 1997 75.40 15.60 8.40
093
/2012/ / 85-98
1965( 771~403 )
(Tan, 1998; Tan et al., 2001)
( 2000 Tan et al., 2001)80.3%
18.8% 0.4%83.1% 15.2% 0.8%
5.
( )Figure 5. Low magnification SEM image (SE) of the large bronze spearhead fragment. Note the thick layer of internal corrosion, the un-corroded metal core and the residual ceramic mould in the core (right hand side of image).
A
B
6. ( )( )
Figure 6. Low magnification SEM image (SE) of the large bronze spearhead fragment. Note the thick layer of internal corrosion, the un-corroded metal core and the residual ceramic mould in the core (right hand side of image).
7. () (SE)
Figure 7.Low magnification SEM image (SE) of the cast, dendritic microstructure (darker, feather-like structures) in the large bronze spearhead fragment. Note the gas porosity from the casting process.
A
B
094
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
68-74%23-29%
( 2000 Tan et al., 2001)
79.46% 19.02% 0.76%
()
+
+(Tan et al., 2001; Tan &
Liao, 2011)
4
Lin et al.(1997)X-
(XRF)
(Hughes & Rowe, 1991)
2
1 2( 12)
( 13)
095
/2012/ / 85-98
8. (SE)
Figure 8. High magnification SEM image (SE) of the eutectoid structure in the large spearhead fragment. The lighter structures are the tin-rich -phase.
9. Figure 9. The copper-rich -phase corrodes first, followed by corrosion of the tin-rich -phase.
10. (SE-SEM)Figure 10. Dendrites revealed by differential corrosion in the patina of the large bronze spearhead (secondary electron SEM image).
11. 2Figure 11. Widmanstätten structures visible in the patina of Sword 2 (light microscope image).
12. 1 2Figure 12. The patterns on Swords 1 and 2 are identical.
13.
Figure 13. The scratches in the white metal pattern are much more sharp and clearly defined than where they cross into the patinated area.
096
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
( 14)
2
15
(1)
eBay1
14. Figure 14. Suggested method for making the pattern.
097
/2012/ / 85-98
(2)75%
17% 3%2
(3)16
2(
)5-6
(4)
Hughes & Rowe(1991)1 150
60 50 50
24
( 3)(5)
4. 4
15. Figure 15. Soil particles adhering to the patterned area (light microscope image).
16. 2
Figure 16. The tool marks on the pommel of Sword 2 could only have been made with a rotary grinding tool, i.e. a flexible shaft electric drill.
X-4 2
098
Journal of Cultural Property Conservation/2012/No.22/pp.85-98
()
X-
Elizabeth E. PeacockHjarle Hjeleng
Ying-da Yu
* Gordon Turner-Walker*
Associate Professor Department of Cultural Heritage Conservation, NationalYunlin University of Science and TechnologyDoului, Taiwan, R.O.C.
Wang, Chu-ping
Research and Object Conservator Department of Registration and ConservationNational Palace MuseumTaipei, Taiwan, R.O.C.
:2012/07/27:2012/12/10
Received Date: 2012/07/27Accepted Date: 2012/12/10
[1] 1992
[2] 20001 111-146
[3] Allen, A. J. (2001). Allen's Authentication of Anc ien t Chinese Bronzes . New Zea land: Allen'sEnterprises Ltd.
[4] Collins, W. F. (1934). The mirror-black and "quicksilver" patinas of certain Chinese bronzes. Journal of the Royal Anthropological Institute of Great Britain and Ireland 64: 69-79.
[5] Derui , T. (1998) . Histor ische chinesische B r o n z e g u ß t e c h n o l o g i e m i t b e s o n d e r e m Schwerpunkt auf der Erzeugung zinnreicher O b e r f l ä c h e n . I n M e t a l l r e s t a u r i e r u n g –International Conference on Metal Restoration
organised by the Bavarian State Conservation Office and the German National Committee of ICOMOS, Munich 23-25 October 1997 (Martin Mach ed.) . ICOMOS/Hefte des Deutschen Nationalkomitees XXIX: 56-63.
[6] Hughes, R. & Rowe, M. (1991). The Colouring, Bronzing and Patination of Metals. US: Watson-Guptill.
[7] Lin, E. K., Wang, C. W., Yu, Y. C., Liu, T. Y., Tan, T. P. & Chiou. J. W. (1997). Particle induced X-ray emission (PIXE) in multielemental analysis. Chinese Journal of Physics 35: 6-11.
[8] Sco t t , D . A . ( 1991 ) . Me ta l l og raphy and Microstructure of Ancient and Historic Metals. Singapore: Getty Conservation Institute/Archetype Books.
[9] Tan Derui et al. (2001). A Study on the Making Technique of the Lozenge Pattern on Bronze Weapons in the Eastern Zhou Period. Chinese Archaeology. 1: 76-80.
