Parker Brothers and Parker/Remington shotguns were ALL case colored using the bone charcoal method. They never used cyanide to case color their frames. The mellow hues they achieved cannot be duplicated using cyanide. Del Grego used cyanide extensively and is easily recognized, but also used bone charcoal as well, though it is quite gaudy. Parker Reproductions used some unknown process to mimic case colors that wears into a really beautiful coin patina, but it is neither cyanide or bone charcoal.
JR
