I can not tell you what it is, but the blue ink is not printing (jet dried?) And made me think of printers with 1 color cartridge has always annoyed! Photo prints go sometimes not :-( but you do not want to throw away the whole cartridge still the same, so the old Brother printer is still next - gift horse in the mouth is finally not kuckt ;-) Conclusion: when the ink runs out, Samsung printer is sure mothballed or passed ...