how do you want to make it?
I'd make full-sized copies, cover with clear tape, then use an EXACTO to cut out the metal portion of the design.
If outer diameter is 3/4" then use a 1" hole saw to cut out 2 round, metal circles. Measure inside of hole saw, make sure it is the correct size. You dont want the hole that the hole saw makes, you want the piece of metal that ends up inside the hole saw.
Trace out on metal using template, drill holes into green areas, then get a small file in there and file down. Put metal piece in flat piece of clay and pour green resin into the green areas.
If you have a 3d Printer, make the circles black and the green areas white using WindowsPaint or some other pic editing software. Load into 3d print software as a jpg, check make darker areas thicker. Print, then pour green resin into shallow areas.
Print full size, cut out circles and designs over styrene. Paint metallic. Fill gem areas with green resin
EDIT: Be sure inner diameter of hole saw is the size of the OUTER Diameter of the rings you want to make