18k solitaire heart diamond woman's ring - STL

Hi,

I need a STL cad file made up for a woman's 18k solitaire heart shape diamond ring. This will be printed and cast to make the ring.

It will be made in 18k gold, total final weight: no more than 3.2 grams (without diamond)

The heart diamond is 0.3 carat, approximately: 4.5mm x4.5mm x 2.6mm depth

Diamond should be set with a 3 prong setting.

The shank should be approximately 1.8mm in thickness.

Size of ring should be ring size UK: L

Diamonds:
1 x 0.3 carat heart diamond (4.5mmx4.5mm.2.6mm)

CAD should look like attached images.