Jade Jagger (yes, daughter of you know who) has been designing jewellery for several years now. She was the former creative director for Garrard, and continues to sell her own pieces through her own site and others.
This 18k yellow gold ring, highlighted by Harper’s Bazaar, is available from Shop Latitude. Made to order, it ships in 6-7 weeks and costs USD $$2,750.
IntoTemptation.....jewellery musings 
I really like this ring
Some of her designs are really great. She doesn’t seem to be getting as much media coverage since she left Garrstd though.