The cavosurface gingival bevel for a class II cast gold inlay preparation should be
The gingival bevel should be 0.5 to 1 mm wide and should blend with the lingual secondary flare.
Sturdevant Operative Dentistry 7th edition page. e105
0.5 to 1 mm wide and blend with secondary lingual flare
0.2 to 0.3 mm wide and blend with secondary lingual flare
0.2 mm wide and blend with secondary lingual flare
3 to 4 mm wide and blend with secondary lingual flare