A spectroscopic study has been made on various mixtures of the mercurous halides HgX(X=F, Cl, Br, l) photodissociated from the mercuric salts by ArF excimer laser excitation at 193 nm. The combination of two or more different halides of mercury within a laser cavity, operating under similar conditions to the single HgX lasers, is a logical step forward in extending the tuning range within the visible spectrum. The effect of such mixtures upon the laser absorption bands for both photolytically pumped and electrically excited laser emission and the production of interhalogen compounds and their effect on laser emission is discussed. For certain mixtures, a continuous fluorescence emission band was observed from 420 nm to 560 nm with further emission at 340 nm. It was deduced that mixed laser emission would occur in four bands: 340 to 343 nm, 440 to 445 nm, 493 to 510 nm and 533 to 565 nm; this has been confirmed by recent laser measurements.