What specifically is a Cote du Rhone blanc?

[hotwine]

Several white wines are produced in the Rhone. Among them are Grenache Blanc, Roussanne, Marsanne, Piquepoul, Clairette, Picardan and Viognier. (Larousse, pg 244). Don't know what would go into a CdR Blanc, but maybe the grapes are listed on the bottle recommended by your friend.