It seems in the past at least for Ashkenazim the wedding rings had houses on them (some of them had a hinge on the roof so that the house opened, from the top)
.
See.
https://www.pinterest.com/kerrydallas/judaica-house-rings/
http://www.hebrewbooks.org/pdfpager.aspx?req=53281&pgnum=36
http://www.hebrewbooks.org/pdfpager.aspx?req=53281&pgnum=38
https://www.google.com/search?q=טבעת+קידושין&prmd=ivn&source=lnms&tbm=isch
But it seems not to be used anymore.
Are there Any halacha or Torah Sources that speak about this type of ring?
I understand that there is halacha E"H 31.2 about no stones but most of the houses do not have stones
(Does anyone know what the hinge was for?)