Diamonds only...
As far as we know the DOC has been loaned just the one diamond collet necklace (first worn July 2007):
DOC 60th Birthday photo.
It was stated in the official release at the time that the necklace was provenance of the Queen Mother.
The cover of the
Shawcross book shows the Queen Mother wearing two diamond collet necklaces.
There are three diamond collet necklaces which were left to the Crown by Queen Victoria.
Quoting Suzy Menkes:
The Diamond Collet (161 carats)
Necklace of 28 brilliant collets made from diamonds taken from the Garter Badge and Sword for Queen Victoria;
Detachable pendant also used in the Crown of Queen Elizabeth the Queen Mother. The diamond drop was originally part of the Timur Ruby necklace;
Necklace reduced and drop diamond earrings made 1937 (two large stones removed and replaced with three smaller stones).
Two Diamond Collet Necklaces
A diamond collet necklace of 45 collets
A diamond collet necklace of 42 collets
Spare 154 collets (see below).
Judging by the size and number of diamonds, my guess is Camilla was pictured wearing the 28 collet necklace.
The pic of
HM and HH the Aga Khan shows her wearing what Menkes describes as "the triple strand diamond collet necklace with triangular motifs. Made up in 1950 by George VI from spare royal gems." (found rolling around in a box stuffed in the back of a cupboard?
)
What we call the 'waterfall brooch' is referred to by Menkes as "Queen Victoria's diamond tassel brooch".
.