But for all its virtues, the harsh blue light of a xenon discharge lamp would look awfully out of place in a classic 1970s or even 1980s sportscar.

Though costlier, xenon allows a discharge lamp to start far more quickly.

A spark discharge between two electrodes produces an "ionised gas tube" in the xenon gas-filled lamp piston through which electric current flows which in turn causes the gas to light up.