This month we are going back to the Bronze Age to a time when the production, fabrication, development and use of metals was very much in its infancy. The late Bronze Age knife or razor shown below was found near Swaffham and was probably cast in a two-piece clay mould around 800 to 700 BC.
The metal is Bronze which is comprised of copper and tin alloyed together, but it probably also contained a deliberate addition of lead, as the metal-workers of the time had already discovered that this made the metal more fluid when molten and therefore improved the casting process (1). As the drawing shows the leaf-shaped blade is still in surprisingly sharp condition.
Full details of the knife can be seen at www.finds.org.uk using search reference NMS-5BFE67.
Ref 1: A Sample Analysis of British Middle and late Bronze Age material using Optical Spectrometry, M Brown and A Blin-Stoyle.