I attempted to make lye today, with questionable results.
I mixed 1/2 mol of quicklime in water, and got the expected:
Exothermic reaction heated water
I then added 1/2 mol of slightly suspect potash (it's brown rather than white, see potash discussion) and got pretty much what I expected: a chalk precipitate and a slightly brownish liquid. I had used a lot of water, so the boil-down took forever. I stopped when I had maybe twice as much fluid as it would take to dissolve a half mole of lye, and transferred the liquid to another vessel, figuring that the precipitates so far would be something other than lye. Boiling the remainder dry gave a dark brown paste, then powder. It was highly alkaline.