From Franck „History of Famous Jewels and Collections“ board :
This list was only made from a juridical point of view following the information we have in our possession. Obviously, we do not have access to the protocol of divorce.
Nevertheless, it is logical that, jewels given by British Royal Family or as « Princess of Wales » would be kept, according to tradition within the Royal family.
“During her lifetime, Diana will keep the jewelry and family heirlooms she was given as Princess of Wales, but, according to tradition, they will be passed down and kept within the royal family ».
I. Jewels return to the vault (Queen Elizabeth II):
a. From the British royal family :
i. The Cambridge Lovers’ knot tiara;
ii. Diamond and emerald art-deco choker;
iii. The Swiss Federal republic’s watch ;
iv. The pearl and diamond earrings (as a wedding gift from Queen Elizabeth II) ;
v. The family royal order;
vi. Large sapphire and diamond brooch converted in a necklace (wedding gift from Queen Elizabeth the Queen Mother)
b. From Prince Charles :
i. Diamond and emerald art deco bracelet as a wedding gift + earrings (gift from prince Charles) + an emerald ring also a gift from Prince Charles;
ii. A floral cluster diamond ring with a Bostwana stone (2 carats) from Prince Charles;
iii. A grey and white pearl necklace;
c. Official gifts:
i. The Oman sapphire and diamond demi-parure;
ii. The diamond and sapphire tassel necklace – Gift from The Emir of Qatar; certainly broken into two bracelets,
iii. The Saudi Arabian ruby and diamond demi-parure;
iv. Emerald and diamond demi-parure (necklace and earrings); certaintly a gift from Golf,
v. Gold jewels given in 1989 during the Gold tour
II. Jewels worn by the Duchess of Cornwall:
a. The Prince of Wales feathers’ diamond and emerald pendant (engagement present from Queen Elizabeth the Queen Mother – Return to the vault and maybe worn by the Duchess of Cornwall)
III. Jewels worn by the Duchess of Cambridge:
a. Her sapphire and diamond engagement ring;
b. Collingwood diamond and pearl dangle earrings; (wedding gift)
c. A diamond and south sea pearl earrings;
d. Pearls a from ruby, diamond and pearl earrings;
e. A triple-row pearl and diamond spacer bracelet (bought be Princess Diana in 1989)
f. A four-row pearl bracelet worn at the state diner b by Queen Beatrix of the Netherlands in 1982 (Maybe on loan from Queen Elizabeth II );
Jewels worn by the then Princess of Wales
Queen Mary’s Art Deco Emerald Choker – Catherine Princess of Wales Emerald choker the Ladies of India Necklace
Emerald choker was called the Ladies of India Necklace
IV. Jewels worn by the Duchess of Sussex:
a. Emerald-cut aquamarine ring; (personal gift)
b. A diamond Tennis Bracelet from Cartier;
c. Gold and Sapphire bracelet; (personal gift)
d. Diamond and Sapphire Butterfly Earrings -made from an unknown gold disk with stones + diamond motifs, worn once in 1985; (personal gift)
e. A cartier tank française watch; (personal gift)
f. Two small diamonds from her collection;
V. Jewels given by princess Diana during her life :
a. A sapphire and gold necklace with the Prince of Wales feathers as a pendant from the National Association of Goldsmiths and designed by Lexi Dick; earrings to match (Wedding gift);
b. A gold and cross necklace (for a charity Event in September 1997 Canceled)
VI. Jewels on loan (Not including from Queen Elizabeth II and her mother) :
a. The Spencer tiara;
b. The swan Lake pearl and diamond necklace + earrings;
c. A large amethyst and diamond cross pendant (a loan from Garrard);
VII. Jewels unworn and certainly/maybe inherited by her children:
a. Wedding gifts:
i. The Saudi Arabian diamond and sapphire suite;
ii. The Gold choker with pearl fringe and multi-gemstone necklace from the Crown Prince and Crown Princess of Jordan (Including a central emerald, turquoise, amethyst, coral, pearl and diamond);
iii. A set of jewellery crafted from coral and gold from the heir Apparent of the State of Qatar;
iv. A diamond watch (Lady Kalla watch);
v. A five-row pearl bracelet with a diamond flower clasp (wedding gift from the UAE) + a pearl necklace with a sapphire clasp;
b. Personal gifts:
i. The double strand pearl, gold and diamond bead necklace with a central diamond heart (bought by Princess Diana in 1982);
ii. A diamond flower brooch (Gift from her friend Adrian Ward-Jackson);
iii. A jade necklace and earrings from the oil Tycoon Armand Hammer (never worn in public);
c. Officials’ gifts given in UK (personal, further to the divorce’s settlement:
i. A necklace with a centrals stone – The necklace has no stones but raw gold (gold nuggets?) in a gold frame hanging from a blue silk cord. -ship launching present – The present was paid by Wärtsilä shipbuilding company, made by Tillander and given by the president (never worn in public) + a bracelet (Information from Margot);
ii. A sapphire and diamond watch (gift, which was presented to her at the 1983 International Spring Fair in Birmingham;
d. Gifts or loan with unknown provenance:
i. The graduated diamond flower cluster necklace (mostly on loan from Queen Elizabeth II );
ii. The six-row pearl choker with a large pearl surrounded by diamond + earrings (mostly on loan from Queen Elizabeth II );
iii. A seven-strand pearl choker with diamond and ruby spacers;
iv. Ruby and diamond necklace worn only once in Venice;
v. An amethyst and diamond demi-suite;
vi. Aquamarine and diamond demi-parure (comprising dangle earrings and a bracelet);
vii. An aquamarine and pearl bracelet;
viii. Gold earrings bought during her life;
Thank you to Franck!