What is the Quality of Gems TV stock (Please see inside)

Hi I hope this isn't too off topic but I'm concerned about my Dad - he
seems to have become obsessed with buying the female members of the family
as much Gems TV stuff as he can get hold of - he is convinced it is all top
quality stuff at bargain prices. I'm no expert but having looked at their
stuff, examined the wording of their descriptions - I am sure that they
can't possibly be selling one thousand dollar rings for one hundred & fifty
dollars. I even saw a Tanzanite piece the other month supposedly worth
thirty thousand dollars being offered for four thousand. I think they sell
low grade stuff at low grade prices - what do the experts on this forum
think?
And are there any other similar operations or shop chains in the US &
Europe we should avoid buying from?
regards
anyone