I agree that it's probably blush. I have used only the thick epoxy with 1 to 1 hardener, and the thin epoxy with the 2 to 1 hardener from USComposites. I have never seen any blush from these mixtures. I am happy with the USComposites epoxy I use here in Texas (it's hot). RAKA also worked fine for me though it was much faster. I did detect a very slight amount of blush with the RAKA. It's best to treat all epoxies as though they blush and work accordingly. RAKA may very well be higher quality (though I can't say yea or nay), but for me the quality and price of the USComposites stuff is fine. We need everyone who has experience with any of the epoxies we use to post their experiences and opinions.