Artemisia, checked out your website.
Camilla might have received as wedding gifts or inherited some Parker Bowles items.
Here's a list of the wedding gifts Ann de Trafford received when she married Derek Parker Bowles, don't know if it will be of any help to you.
Necklaces
diamond necklace
pearls
necklace (not specified)
Brooches
diamond clip brooch
diamond & emerald brooch
3 diamond & amethsyt brooches
diamond & sapphire brooch
diamond & sapphire clip brooch
diamond brooch
diamond clip (not stated as brooch)
bracelets
pearl & emerald bracelet
diamond bracelet
platinum bracelet
bracelet (not specified)
rings
2 diamond & sapphire rings
diamond and ruby ring
double diamond ring
ring (not specified)
diamond ring
charms
diamond charm
tiaras
diamond
watch
diamond
Also keep in mind that jewelry that was owned by Camilla's mother might not been dispersed until after her father sold the house in 1996 and some pieces that people attribute to Charles might infact be pieces owned by her mother or grandmother.
Some of Camilla's jewelry might have been given to Sonia by Margaret Greville, whom Sonia describes as a very indulgent godmother.
The pictures I've seen of Alice & Sonia showed them wearing single & multi strand pearls of various lengths and bracelets, including charm bracelets and very few if any brooches. Alice's pictures are from 1890-1935. Sonia 1903-1960 mostly from the 20's & 30's.
In a 1936 photo of Camilla's mother Rosalind's is wearing the chocker with the small diamond enhancer.
http://beinecke.library.yale.edu/dl...TEM.asp?pid=2002043&iid=1005733&srchtype=ITEM