At day seventeen newborn gerbils will open up their eyes, they will have most of their fur as well then. At this point their will be very nervous because it's an entirely different world so be patient and gentle with handling them. Good luck with your gerbils :D.
Wonderful gallery of a gerbil litter from birth to three years of age: http://www.egerbil.com/gerbil_birth_to_three_years_of_age