What technique was used to render the face in this Funerary Mask from Grave Circle A, Mycenae, Greece

"we that are young, shall never see so much, nor live so long." the weight of this sad time we must obey, speak what we feel, not what we ought to say. the oldest have borne most; we that are young shall never see so much, nor live so long.

explanation:

the answer is

he used natural lighting to create convincing space and render solid forms.