Hi Robert thank you for your question. France has used a variety of marks and hallmarks since mid-13th century, including guarantee (Purity), Charge & Discharge (Duty/Tax), Countermark (Assay), Census etc.
Most regions and towns had their own marks or standards, which varied extensively over time. Most gold, silver or precious metal items made in France after 1838 have only two marks: the Guarantee mark and the maker's mark.
An Eagle Head is the hallmark for 18ct gold in France, since 1838 until today.
