The milky color disappeared when it dried. Thank you. Left was the orangey back (mask) and the silver colloid layer on the emulsion side. Some mottling and...upon inspection directly on a 40W bulb, I can see faint images now. Very faint. A toddler being held by a woman in sitting room chair. A man with a cap. It looks like they may have been taken indoors and maybe, vastly underexposed. That, plus 40 years of base fog doesn't help ;-)
The mask is much denser than C-41. Held up to the light at arms length, you can barely see through it. I guess the yellow colloidal silver layer doesn't help the transparency either.
I tried to scan but the scanner can't peek into that opacity. It only sees black. I played with a variety of settings but I only get noise. Maybe I'll try to make a cyanotype with it? Given enough time, it should peek through and give me something.