Prepared and tested in production STL and 3DM source files for editind/modifying.
Ring diameter 16.5mm
Gems: 44x 1.2mm gems placed in two rows(22x2)
Some dimensions are shown on screenshots.
Model volume is 473 mm^3, so estimated weight is
OBJ's are untested (anyway OBJ format is useless for production), exported from Rhino as mesh and as NURBS. I added OBJ's just for better publishing and placement after stupid recomendations of CGtrader (probably for smart heads from CGt quantity of junk and thumbs is more important than quality of models).