STL 3D model.
Model is ready for 3D Printing.

Geometry: Polygonal
Polygons: 347254
Vertices: 212639

This is a good mesh:
Mesh does not have any degenerate faces.
Mesh does not have any extremely short edges.
Mesh does not have any non manifold edges.
Mesh does not have any naked edges.
Mesh does not have any duplicate faces.

Size_1

Ring size : 8 USA

diameter 18.00mm

weight:

7.4g-silver 925

9.9g-gold 14k

11.1g-gold 18k

Gems:
round 72x1.70mmx1.70mm

size_2

Ring size : 6 USA

diameter 16.50mm

weight:

5.60g-silver 925

7.50g-gold 14k

8.50g-gold 18k

Gems:
round 72x1.50mmx1.50mm

Note:
Ring diameter can be easily changed only by changing the overall ring size.

Dimensions:
you can see all dimensions in Illustrations.