Dark Green Locomotive Enamel

[Atomsk]

At the risk of duplicating any number of past posts, I have some questions about PRR's Dark Green Locomotive Enamel (DGLE).

I've seen anecdotal sources that say PRR made up DGLE paint by adding X amount of dry pigment to a 55-gallon drum of black paint. However, these sources vary on what pigment they used, and why they used this pigment in the first place.

First off, the misnomer "Brunswick Green" comes form the "colour" used used by railroads in the UK, starting with the Great Western, and continuing through the early years of the consolidated BR system. It refers to a green color created using copper based pigments.

Some sources refer to DGLE also using copper pigments, while others refer to Chromium based pigments.

Also, some sources state that PRR added pigment to black so that it would weather to green, instead of gray. Others indicate that the pigment provided corrosion protection. The second theory would support the use of Chromium compounds (such as Zinc Chromate).

Does anyone know of a primary source that can clear up the contradictions in these stories?

What was the composition of DGLE?

Also, did PRR paint steam locomotives, other than T1s in DGLE?

I can't recall seeing color photos of PRR steam weathered to anything but slate gray. From what I can tell, PRR Diesels and GG1s (and T1s as well) have an obvious greenish tint to them when heavily weathered.

[Pennsyjohn]

PRR's Brunswick Green was, according to a mix instruction I found at the historical society's website, is 1 gallon of Bright Green to 50 gallons of Black.
That is one hell of a dark green. No mention of dry colors.

Pennsyjohn

[ExCon90]

You had to see it with the sun hitting it just right on a bright day when it had been freshly washed to get an idea that there just might be a little bit of green in there.