"...parkerizing finishes are gray While others are black..." The chemicals used. Grey Parkerizing is Zinc based. Comes out different shades of grey according to the metal it goes on. Supposedly it does not go on SS or gas tubes of M1 Rifles. Mine took commercially done Parkerizing with no fuss though.
Black is manganese based.
"...colors of phosphate finishes are green..." There is no such thing as green Parkerizing. Any green tinge is the result of long term storage in Cosmoline. Nobody has ever been able to figure out how to duplicate it either.
Black is manganese based.
"...colors of phosphate finishes are green..." There is no such thing as green Parkerizing. Any green tinge is the result of long term storage in Cosmoline. Nobody has ever been able to figure out how to duplicate it either.