From an O. Henry short story, "Roads of Destiny":
"I am positive that never during the eleventh and thirteenth centuries did Baron, Troubadour, and Worker amalgamate as harmoniously as their parallels did that evening at old man Ellison's sheep ranch."

O. Henry has a way with words. This use of "amalgamate"
seems just right to me. A dentist takes silver powder, adds
a bit of liquid mercury, and with only a minimum of coaxing the two unite into a substance with new and valuable properties.