It lacks the beauty and elegance I associate with Cartier. Maybe it looks better when being worn.

Often many of the leading jewellery houses tend to try and buy back jewels from their history when they come to auction. Maybe the fact they didn't try (or were unwilling to spend ££££) suggests that Cartier either doesn't rate it amongst their past work as being importance enough to try and buy or simply they don't accept it as one of their's.