Bright field photomicrograph of an etched cross section across a French 18th-century brazing joint between two cast brass elements. The section shows the typical large grains and dendritic structure of the two cast elements as well as the so-called Widmanstätten microstructure of the quickly cooled, high-zinc brass brazing metal (green overlay). Note that the two metals did not melt into each other. Etched with a solution of 25% hydrochloric acid and 8% iron chloride in industrial methylated spirit. Cross-section prepared by Yannick Chastang.