Here’s a photo taken in his studio. I can see terra verte (which I’ve also heard him mention in interviews), maybe cobalt blue, a sienna, and maybe cadmium? yellow. Not sure what the reds are. You can probably simulate his palette with umbers, ochres, and siennas, earthy greens such as terra verte, a couple of blues (maybe cobalt and ultramarine), black, white, and brighter yellows and reds (cadmiums) when needed. I have to say though, that I never dealt with powdered pigments, so I’m not sure about safety issues in dealing with pigments that may be toxic such as cadmiums.

You’re welcome. I was just going through my Wyeth books. The only thing I could find relating to his palette was this quote about tempera: “I loved the quality of the colors: the earth colors, the terra verde, the ochers, reds, the Indian reds and the blue reds are superb”. Not sure what he meant by “blue reds”. In another place he talks about using alizarin crimson as an underpainting for the greens in his painting “Pine Baron”. I think his palette was earth-tone based, but he used whatever he had to in order to get the effect he wanted.