The knife was made with iron that came from a meteorite, according to an article in the journal Meteoritics and Planetary Science published online last month.
The first knife has a blade of gold, while the iron dagger has a gold handle, rock crystal pommel and jackal-decorated sheath.
The iron knife has puzzled researchers for 91 years, partially because ironwork was rare in ancient Egypt.
Despite being more than 3,300 years old, the iron dagger shows no signs of rust, according to The Guardian.
Researchers from Milan Polytechnic, Pisa University, and the Egyptian Museum in Cairo studied the metal makeup of the iron knife using non-invasive, portable X-ray fluorescence spectrometry.
The nickel and cobalt ratio in the dagger blade is consistent with that of iron meteorites that have preserved the primitive chondritic ratio during planetary differentiation in the early solar system.