You should be able to walk into any jeweler and have them test it - but always get a 2nd opinion - or sometimes a 3rd -
took a ring (like 25 yrs ago) I found on asphalt of parking lot and had been run over 100 times and was beat up -- to 3 places - 1st said it was fake stone and junk metal
2nd said junk stone and platinum metal (which is weird that they would put junk in plat.) so I went to a third - this guys had a degree in gemology
and said others thought it was fake because it was an early cut stone and platinum mark was an older mark not used in like 100 yrs
a 4th place verified this and bought it
I have my own testers now
here is what you do, I know what I'm talking about
take an old tooth brush and clean it with some soap and warm water
than turn the ring around and take any newspaper or any piece of paper with text on it.
try to read the text through the diamond from the backside of it
what do you see? if you can see the letters (if they appear to be strange) then the stone is likely fake, however if you are absolutely unable to see the letters then its likely real
This "test" is almost impossible to do when in a setting.
here is what you do, I know what I'm talking about
take an old tooth brush and clean it with some soap and warm water
than turn the ring around and take any newspaper or any piece of paper with text on it.
try to read the text through the diamond from the backside of it
what do you see? if you can see the letters (if they appear to be strange) then the stone is likely fake, however if you are absolutely unable to see the letters then its likely real
If you knew what you were talking about you would tell him to get it tested or get a tester himself.