How is Salem an example of "a crucible?"
Salem becomes an example of a crucible because it is tested through an intense period of heat and pressure. The accusations test Salem to its very core. Some of those tests are how strong the bonds between individuals are or how much Salem will believe in Christian goodness and righteousness and not in their own "darker" natures. These "crucibles" become the fundamental tests for Salem, as it must recognize its own identity in the face of the trials. At the same time, Salem's endurance of the witch trials force a fundamental crisis of conscience, which becomes a crucible of sorts. How individuals respond to the accusations in terms of accepting them on false pretenses, sacrifice others in the process of their own accusations, or demand that there must be a need to "not bring harm to another" all becomes critical elements of the crucible that are being faced by the people of Salem. It is in this vein where I think that Salem endures its own crucible, something that is tested and whose results are seen in different forms with the different responses from characters in the drama.