Grit was a type of material similar to dust. (PROSE: Henry Van Statten [+]BBC webteam, Who is Doctor Who? (BBC, 2005).)
History[]
In an interview hosted by Mickey for his website in early 2006, Henry Van Statten recalled the experience of having moondust — alien grit — run through his hands for the first time was "ultimate", as he could not physically travel to another world despite his interest in aliens. (PROSE: Henry Van Statten [+]BBC webteam, Who is Doctor Who? (BBC, 2005).)