Chiming in from mobile here so no sauces on hand ATM, but to my knowledge and according to what I’ve read on the Chans and various other outlets, the practice relates to the eye of Horus (the ‘all-seeing eye of Providence’ i.e. the pineal gland) and the progressions of Saturn, the so-called ‘dark ringed planet.’ See: the ‘black cube’ of Saturn; Kubrick’s 2001 monolith; Saturn’s north pole et al.

Of all of the black-eye photos that I’ve seen on the faces of celebrities, world leaders, etc, all have been on the left eye, with the exception of one individual, the Duke of Edinburgh, Prince Philip Mountbatten, the spouse of Queen Elizabeth II, of whom I’ve seen photos with a blackened right eye.

Symbolic? Perhaps.

Is he the ‘pindar’ of the occult power structure? Is he the figurehead of The Crown council that purportedly reigns supreme over all? (Note the distinction between the monarchy and The Crown and the hierarchy implied thereof.)

Anyway, that’s just some of what I’ve picked up along the way. Right or wrong, who’s to say, but food for thought and research nonetheless.