Cardinals during a consistory ceremony (Consistoire; Konsistorium) celebrated in Saint Peter's basilica by pope Benedict XVI on November 24; 2012 at the Vatican. -The cardinal's red scarlet hats : the birretta (la barrette; das birett ) and the Zucchetto (calotta; la calotte; Pileolus).- Their scarlet colour signifying the blood of martyrs; or those willing to die for their faith.