Object: Flat Axehead (Bronze Age)
Period: Bronze Age to BRONZE AGE (-2200 to -1950)
Material: Copper alloy 
Found: Luddendenfoot, Calderdale, Calderdale (Yorkshire and the Humber)
Discovery method: Metal detector
Length: 140.5 mm
Thickness: 12 mm
Weight: 336 g
Description: A cast copper alloy flat axe of Early Bronze Age date, about 2200 BC - 1950 BC. The axe is probably a broad butt flat axe of Migdale type (decorated Variant) and is decorated with rain pattern.



The blade flares from about two thirds of the way from the butt, with angular shoulders; this may have been secondary hammering; the cutting edge was narrower to begin with. The blade is 70.3mm wide at the tips, and flares from 46.2mm wide at the change of angle. The butt is 33.2mm wide half way along, and has a rounded end. The cutting edge is damaged, and is mainly missing. It is 6.2mm thick at the blade end, where the cutting edge should be. The axe is 11.9mm thick in the centre, and tapers to 6.8mm thick at the butt. The sides of the blade are not symmetrical, the change of angle being more pronounced on one side. If it was symmetrical originally, the axe must have lost a lot of metal and it seem more likely that the sides were never exactly matching. There are no flanges, but the sides do become more square in the centre of the axe. Most of the original surface of the metal is missing at the butt end.



One face is better preserved than the other, and it is decorated with faint longitudinal grooves covering the blade half of the axe (rain pattern). Each groove is only about 1mm wide and they seem to be long, continuous lines rather than short dashes. The other face of the axe has less of the original surface surviving, but traces of a similar pattern are just visible. The axe has been treated with an oil, PEG or wax coating, and it appears that it was placed on this face while the coating was still wet, so an impression of the cloth or polyroll it rested on is obvious; a pattern of small circles or dimples.



The axe has a dark green to black colour and is in a stable condition, though it has suffered from corrosion. Overall, it is 140.5mm long, 70.3mm wide and 12mm thick. It has a mass of 336g.



Ref. Schmidt and Burgess 1981, nos. 196-209. Plates 16 and 17.
Notes: Energy Dispersive Spectroscopy on the SEM



by Stuart Fox of the University of Bradford, Faculty of Life Sciences, Archaeological Sciences.



Spectrum processing: No peaks omitted



Processing option: Oxygen by stoichiometry (Normalised)



Number of iterations = 3



Standard CACO3 1-Jun-1999 12:00 AM

Cu Cu 1-Jun-1999 12:00 AM

Sn Sn 1-Jun-1999 12:00 AM






Element

			
Weight %

			
Atomic %

			
Compd %

			
Formula

		


C K

			
3.03

			
8.54

			
11.11

			
CO2

		


Cu K

			
65.48

			
34.86

			
81.97

			
CuO

		


Sn L

			
5.45

			
1.55

			
6.92

			
SnO2

		


O

			
26.03

			
55.05

			
 

			
 

		



			
Totals

			

			
100.00

			
 

			
 

			
 

		



Axe head 0.28% As. push







			
Element

			

			
Weight %

			
Atomic %

			
Compd %

			
Formula

		


C K

			
3.03

			
8.53

			
11.09

			
CO2

		


Cu K

			
65.21

			
34.73

			
81.64

			
CuO

		


As K

			
0.28

			
0.13

			
0.37

			
As2O3

		


Sn L

			
5.44

			
1.55

			
6.90

			
SnO2

		


O

			
26.04

			
55.07

			
 

			
 

		


Totals

			
100.00

			
 

			
 

			
 

		



Qualitative portable X-ray fluorescence (pXRF) analysis of a metal axe: 



 by Seosaimhín Bradley



University of Central Lancashire



Method



The axe was placed in a bench top test stand and the pXRF spectrometer was secured underneath. This was undertaken in order to ensure that the axe did not move during analysis, and that the distance between the surface of the axe and the x-ray beam remained constant. The surface of the axe was corroded and quite uneven in places, so areas chosen for analysis were selected because they were flatter and more even.



Two readings were taken, in two different areas. Each reading lasted 60 seconds and the pXRF instrument was set at 40kV, 15µA, and with no filter applied. The results were gathered by the accompanying software, S1PXRF, which generated a spectra of results. Further analysis was completed using ARTAX software, which identifies the elements that have been detected, and provides the number of counts per second gathered for each identified element. These counts per second were converted into relative percentages to facilitate analysis. This report uses these relative percentages, and is therefore not of absolute elemental concentrations.



pXRF does not detect all the elements that are present, as some elements are beneath the detection limits of the instrument. Only three elements could be reliably determined: iron (Fe), copper (Cu), and tin (Sn). Small amounts of rhodium (Ru) were detected but this is likely to be interference from the spectrometer, as the x-ray tube contains rhodium. The counts per second recorded for each of these elements was converted into a relative percentage. These results have not been calibrated to an external standard and are therefore not quantitative, but can give an indication of the relative percentage of each of the identified elements. The table below shows the results.






Element

			
Relative %

		


fe

			
10%

		


cu

			
52%

		


sn

			
19%

		



The results of the pXRF analysis indicate that the axe is made of bronze. Further work is required in order to determine in what concentrations these elements appear.
Subsequent action: Returned to finder