the light that the glass take from is the atmosphere created using the BIG BALL our trick [HDRI] , I rendered the model on white ground [ not background] , the object take the light and reflection from the ground plane and the BIG BALL textures only and create very realistic effect on the surfaces without to use any transparency. The material setting for this model was take from post # 16

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"Surrender to what it is - Let go of what was - Have faith in what will be "