É a Cruz da Lorena
O roteiro / script confirma isso ..
Carefully lifting up the stone, he reveals...
INSERT: a gold plate in the setting underneath, an impression of the Lorraine Cross of General DeGaulle.
Pesquisa de Imagens do Google para várias versões.
The Cross of Lorraine (French: Croix de Lorraine) was originally a heraldic cross. The two-barred cross consists of a vertical line crossed by two shorter horizontal bars. In most renditions, the horizontal bars are "graded" with the upper bar being the shorter, though variations with the bars of equal length are also seen. The Lorraine name has come to signify several cross variations, including the patriarchal cross with its bars near the top.
The Cross of Lorraine is an emblem of Lorraine in eastern France. Between 1871 and 1918 (and again between 1940 and 1944), the north-eastern quarter of Lorraine was annexed to Germany, along with Alsace. During that period the Cross served as a rallying point for French ambitions to recover its lost provinces. This historical significance lent it considerable weight as a symbol of French patriotism. During World War II, Capitaine de corvette Thierry d'Argenlieu suggested the Cross of Lorraine as the symbol of the Free French Forces led by Charles de Gaulle as an answer to the Nazi swastika.
In France, the Cross of Lorraine was the symbol of Free France during World War II, the liberation of France from Nazi Germany, and Gaullism and includes several variations of a two barred cross.