I'm going to stick to mesmerizing. Laura Nyro, Emma Kirkby, Judith Nelson, Yma Sumac, Janis Joplin, Kate Bush, Ronnie Spector, Billie Holiday, Maria Callas, Elizabeth Schwarzkopf, Stevie Nicks, Aretha Franklin, Patsy Cline, Elly Ameling.
Most unusual/mesmerizing female voice.