Submitted by curator on Fri, 10/16/2015 - 13:48
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Inv. 32-21-100
Sickle, folded in half
A notch cut from the inner, working edge: magnification, 200x
Etchant: Klemms III
(Sn, <0.034%; As, 0.14%; Ni, 0.055%)
The surface of this tool is heavily penetrated by pitting and intergranular corrosion. In sound areas of the metal, however, the microstructure consists of polyhedral grains that, in their twinning and slight distortion, are indicative of an annealing treatment after moderate cold-working The inclusions have the same rough and mottled appearance as those in other items in this project (e,g., the two holdfasts, 31-52-259 and 31-52-361), and like them, most likely are remnants of non-metallic material (matte) that became entrapped in the copper during its original smelting.
Microhardness VHN: 142 ± 10 (n=5)
Uniform; data scatter (with the VHN ranging 151 to 126) is most likely due to the presence of microstructural porosity.
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