Fig. 12
From: A copper alloy light cannon from Grodno: an example of early firearms from Eastern Europe
Cannon from the Old Castle in Grodno, Sample 4—results of metallographic examinations. a general view of the sample with zones of detailed observations (1–4). b, c microstructure in Zone 1, pores of various size and shape, sometimes with CuS inclusions (light blue). d, e microstructure in Zone 2, pores of various size and shape, sometimes with CuS inclusions (light blue). f microstructure in Zone 3, pores and a CuS inclusion (light blue)