I can't be certain about Reofect, since I cannot track down the name in any of my references. I have messages out to a couple of conservators, who may have encountered this process before. My somewhat-educated guess is that the image was created using a photographic process that is similar to autochrome -- I won't go into that in detail, but it created a color image by means of black-and-white chemistry and three different colors of minute potato starch granules. That's worth exploring, if you're interested.
I am "dyeing" (excuse the pun) to find out more about Reofect, and I will pass along anything I find, unless a kindly expert posts something first.
Best,
Bruce
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Bruce MacLeish
Curator Emeritus, Newport Restoration Foundation
Cooperstown NY
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