Leonardo da Vinci Christ Painting Question

Salvator Mundi (Saviour of the World)

 

 

Italian artist Leonardo da Vinci painted the above master piece with a twist that is causing a commotion in the art world. The orb (sphere) in his hand looks as if it is a solid clear object without a single glare,  reflection or distortion when light passes through it....why?

 

Christie’s this week announced it would be selling Salvator Mundi next month in New York.

Value to be determined.