All gold or platinum jewels made in France are stamped with an assay mark. DFLY uses only precious metals with alloy of high standard purity. Thus, the 18 k (750/1000) is stamped with an eagle’s head mark and 950/1000 platinum is stamped with a dog’s head mark . Only small jewels weighing less than 3 g can be exempt from theses hallmarks (like the stud earrings.)