Arnold Schwassmann discovered IC 3258 on 14 Sep 1900 using a plate taken with the 6" astrograph at the Königstuhl Observatory in Heidelberg. Frost also recorded it on a plate taken at the Arequipa station on 10 May 1904. He noted "R, lbM, diam. 0.7' (Sch 241)."

IC 3258 has one of the highest blue-shifts: -437 to -473 km/sec

400/500mm - 17.5" (4/18/87): very faint, small, round, very diffuse. Forms a pair with NGC 4351 16' SSE.

600/800mm - 24" (5/29/14): fairly faint, fairly small, round, low surface brightness, very weak concentration, 24" diameter.

Notes by Steve Gottlieb