While experimenting with AR view for different Product We came across an issue with Apples AR viewer where for glass (PBR Opacity) it is causing black patch to appear behind (Maybe Shadow).
https://sketchfab.com/3d-models/welcome-5ba96662ba8d4774951f33fead4bf9db
https://sketchfab.com/3d-models/candel-91b2059634e0478eb93777b0b2a726e9
We Tried to find work around but after doing multiple test but with all our experiments we came to the conclusion that Apple AR viewer is not able recognize the glass material and adjust the ground shadow as required.