I am trying to determine if this resistor is metal or carbon film?
Traditionally most of the metal film resistors I've seen have been blue, while most of the carbon film I've seen have been light brown.
However, this particular resistor is gray, and I have seen gray carbon film resistors before (though the gray color was probably some sort of coating, I believe).
If it helps, this resistor was found among many vintage, i.e., pre-1970s resistors. When did metal film come into circulation?