Ronny and Kate Bensimon are members of the Jewish comunity in Australia
Despite the financial situation and status as a bankrupt, Mr Bensimon continues to trade diamonds though a company established by his wife, Kate Bensimon.
The couple are understood to have relocated to Sydney's Bondi Beach earlier this year, after launching a new website bensimondotcom.au that spruiked their "unique passion and an unparalleled approach to working with diamonds, having sourced stones and creating unique jewellery pieces and engagement rings for clients and celebrities all over the world"
Mr Bensimon, who is a bankrupt with debts of almost $10 million, also had a cavalier approach to book-keeping and inventory control.
"I do not know the current location of [the diamond] or who has possession of it."
He claims other diamonds were sold through his stores, but "I am unable to recall when, to who, and in which store each of them was sold".
On his now-defunct website, Mr Bensimon boasted that dealers were happy to lend him diamonds "without so much as a handshake".
When the flamboyant jeweller declared bankruptcy in July 2016, he claimed to have just 17 cents in his bank account.
An investigation by bankruptcy trustees Pitcher Partners attributed some of Mr Bensimon's financial problems to gambling losses totalling almost $2 million with betting agencies TAB, Ladbrokes and Mad Bookie.
Mr Bensimon also purchased $641,570 in Crown casino gaming chips in the two years before his bankruptcy, while another $693,868 was lost trading derivative contracts and other equities.