-Have You Ever Tried to Sell a Diamond?; September Months from Filing to Divorce:7, June MFD:4, Debruary MFD:0/12
-Diamonds are Bullshit; May MFD:3, March MFD:1, March MFD:1
-Diamonds Suck; May, November, February
There is a study which found spike at filing divorces at February; https://www.theatlantic.com/health/archive/2016/08/why-divor...
From this with MFD values it is (not) sensible to say these people want a divorce and seriously don't want to keep the ring and disappointed at the prices they got.
Then there is this (probably doesn't really warrant being called a) study put marriage spikes to October, September and June; https://www.theknot.com/content/is-there-an-off-season-for-w...
From this it is (an even shakier prediction) to say these were asked to (or tasked with) buy a diamond ring, vehemently opposed it and wants rest of the world how to avoid it.