So, here is the film, "Salt of the Earth," from 1954.

Salt of the Earth is a 1954 American drama film written by Michael Wilson, directed by Herbert J. Biberman, and produced by Paul Jarrico. All had been blacklisted by the Hollywood establishment due to their alleged involvement in communist politics.[1]

The drama film is one of the first pictures to advance the feminist social and political point of view. Its plot centers on a long and difficult strike, based on the 1951 strike against the Empire Zinc Company in Grant County, New Mexico. In the film, the company is identified as "Delaware Zinc", and the setting is "Zinctown, New Mexico". The film shows how the miners, the company, and the police react during the strike. In neorealist style, the producers and director used actual miners and their families as actors in the film.
https://en.wikipedia.org/wiki/Salt_of_the_Earth_(1954_film)