This explains the criteria and rationale behind the ban...
// The Reviewing Committee on the Export of Works of Art and Objects of Cultural Interest advised the Secretary of State not to grant it on the grounds that the object is of national importance. With the export ban in place, the item cannot be exported.
The Reviewing Committee assesses each object according to three criteria established by a 1950 export policy committee chaired by Viscount Waverley. There are three Waverley criteria against which an export item is to be judged:
1. History — Is the object so closely connected with our history and national life that its departure would be a misfortune?
2. Aesthetics — Is the object of outstanding aesthetic importance?
3. Scholarship — Is the object of outstanding significance for the study of some particular branch of art, learning or history?
Although Jane Austen’s ring is a lovely cabochon natural turquoise, it’s too simple a design, I suspect, to qualify as a national treasure under Waverley two. There is little of scholarship value in the ring. Jane was known to have simple tastes in jewelry, something reflected in her characters and in at least one letter to her sister Cassandra from May 24th, 1813:
“I have bought your Locket, but was obliged to give 18s* for it-which must be rather more than you intended; it is neat & plain, set in gold.”
It’s a limited area of study, however, and there’s nothing in the correspondence or in the literature about this particular ring. Keeping the ring in country isn’t likely to add anything of major import to Jane Austen scholarship.
That leaves Waverley one, which assesses an object’s significance as an individual artifact or in the context of local history or of a collection, or in its association with important events, people or places. It’s that personal association with one of England’s greatest authors which I suspect underpinned the Reviewing Committee’s decision to recommend an export ban. //
http://www.thehistoryblog.com/archives/20677