I don't know if they do this anymore but perhaps bring it to Cartier and see if they will authenticate it. For some reason I don't think they do this anymore.
That is Definately a fake. Everything about the “hallmark” is off and as for buying “Name pieces” off “Gumtree” ? Don’t.
if it’s like $20 and you don’t mind wearing a replica, sure, but even if it’s actually gold (unlikely) you’d only want to pay gold melt value.
its important to realise that the people who create these fake pieces also stamp fake gold hallmarks so a hallmark is no guarantee. They also make “fake” ring boxes, ribbons, carry bags and even receipts.
"Rings with the 52833A serial numbers and the word Love on the sides are the easy to spot fakes. That serial number is used repeatedly. You can buy them for about $20 more or less. They are probably made of titanium not gold."