My personal shop: http://www.spaziofranco.it
I was testing my new 3D printer, so It required few months researching limits. Now it's perfect and makes happy your girlfriend/wife. You have just to print e buy some steel 'pearl' on Amazon (diameter 8mm). No glue!
Ring ø 18mm.
Speed: 30-40 mm/s
Layer max: .15 mm
Support (lines): over 50°, 20% density. Just a few lines, no big deal.
Print with the flat side on the bottom.