There have been many attempts to assign a conventional spectral class to this star. The Henry Draper Catalogue gives a class of B5. More detailed analysis when the unusual nature of the star was discovered estimated a class of F8 or G0. Later studies gave classes of F0 or F5 to G0. It is considered likely to be a main sequence star with a temperature somewhat hotter than the Sun, but with its spectral lines strongly blanketed by the extreme abundances of certain metals. A catalogue of chemically peculiar stars gives the type F3 Ho, indicating an Ap star with an approximate spectral class of F3 and strong holmium lines.