Here is an article on the famous diamond and platinum Cartier tiara of Queen Elisabeth of the Belgians. After her death, it passed to her son, King Leopold III, to be worn by his second wife, Princess Lilian. After Leopold's death, Cartier repurchased it from Lilian in 1987. There is a great deal of outrage on the internet at Lilian's sale of Elisabeth's tiara and other jewelry which had graced earlier Belgian royal ladies. Critics complain that the magnificent tiara, in particular, ought to have been left to Queen Paola and Princess Mathilde. The fact is, though, that it did not belong to Paola and Mathilde. At that point, it was Lilian's to dispose of as she saw fit. Unlike the jewelry used by other European royal houses, the adornments of the Belgian queens and princesses have never belonged to the state; they have always been the personal property of the ladies in question. In consequence, following the deaths of their owners, they have usually been dispersed, auctioned off or left to heirs outside Belgium. Today, the Belgian royal family has only two tiaras inherited from previous generations; all the rest of the jewelry of Queens Louise-Marie, Marie-Henriette, Elisabeth and Astrid has passed to other hands. This may seem unfortunate, but I find it unfair to single out Lilian for so much indignation, since the dispersal of Belgian royal jewelry is a tradition pre-dating her by far.
Interestingly, Lilian was related to the Cartier family by marriage. Jean-Jacques Cartier, who recently passed away, was married to Lilian's sister Lydia Baels.