Our mandala is indeed an 'eye,' the structure of which…

““Our mandala is indeed an 'eye,' the structure of which symbolizes the centre of order in the unconscious. The eye is a hollow sphere, black inside, and filled with a semi-liquid substance, the vitreous humour. Looking at it from outside, one sees a round, coloured surface, the iris, with a dark centre, from which a golden light shines. Bohme calls it a 'fiery eye,' in accordance with the old idea that seeing emanates from the eye. The eye may well stand for consciousness (which is in fact an organ of perception), looking into its own background. It sees its own light there, and when this is clear and pure the whole body is filled with light. Under certain conditions consciousness has a purifying effect. This is probably what is meant by Matthew 6 : 22ff., an idea expressed even more clearly in Luke 11 : 33. The eye is also a well-known symbol for God. Hence Bohme calls his 'Philosophique Globe' the 'Eye of Eternity,' the 'Essence of all Essences,' the 'Eye of God.' By accepting the darkness, the patient has not, to be sure, changed it into light, but she has kindled a light that illuminates the darkness within. By day no light is needed, and if you don't know it is night you won't light one, nor will any light be lit for you unless you have suffered the horror of darkness. This is not an edifying text but a mere statement of the psychological facts.””

— C.G. Jung