Seeing is believing. Also although Toto's family was rich, in David Balfour's book Elizabeth 's brother-in-law Prince Paul of Yugoslavia described his sister-in-law as looking wretched. "it is heart-breaking to see that beautiful creature come to this.". Also we do not know if they sold jewels after the war years, when life was difficult. It is interesting that we did not see Elizabeth wore the diamond floral diadem that belonged to the family.
Anyway lets go back to the discussion on Grand Duchess Helen & Prince Nicholas. In the books on Marina, Helen did sold some jewels for charity after asking for her daughters's opinion (after all, they were part of their dowry). All the girls agreed and the jewels sold and donation made.