I could be wrong, but from the video it looks like a large citrine set in a cocktail ring. From the looks of it probably from the 1920's. Just my two cents worth from what I can tell from the video. Great find if it is.
Without seeing the ring... errr... not that this even matters really... but could help to get idea of what I am looking at...
Heres dealio...
Anytime something passes 22... and is not marked... and is still subject of uncertainty ...
#1. Hard rub... same spot... BOTTOM of ring where wear has already been rubbing.
IF it passes this... go to step #2 ...
#2. Direct drop... turn ring upside down and drop 22 directly inside... hold and let sit... count to 10 slow...
IF it passes this and you still are not completely convinced...
#3. Destructive test... Take small file and file a line / groove into ring and drop 14 directly... then 18 ...22.
IF it passes 1 and 2 its more than likely good... ONLY do 3 if you plan on scrapping anyway and ring is ugly etc... missing stone whatever.... for it will be ruined after 3.
PS... Also... IF this is a "white" ring... there is Platinum... Rhodium .