I don't think you should just look at the gold content - they can be as low as 30 - 50%. I don't remember the exact ratio. However the earlier issues issued from 1600s are scarcer and are very expensive. A fair number were removed from the country and melted down due to the high gold content.
My partial coin collection http://www.omnicoin.com/collection/gxseries
My numismatics articles and collection: http://www.gxseries.com/numis/numis_index.htm
Regularly updated at least once a month.
My numismatics articles and collection: http://www.gxseries.com/numis/numis_index.htm
Regularly updated at least once a month.



















