18K vs 22K White Gold and setting

Hi Jason, I ,too,am learning about jewelry making, so I can’t offer
any expert advice on setting an emerald but I can give you advice
from experience in regards to wearing a wedding ring with a cabachon
emerald:

My husband and I both carved the waxes for our rings and I chose a
cabachon emerald. That was 18 years ago. Because emeralds are so
soft they do not stand up, in my opinion to the kind of wear a ring
gets when you wear it all the time - like a wedding ring. My emerald
is a sorry looking stone - all chipped and scratched. I’m saving up
for a hard stone to replace it.

Perhaps this advice is not general and someone with more experience
might offer different advice.

Good Luck!
Donna