Hi Iain,
Here are just a few samples of Tuareg swords with double crescent blade marks from German sales of the past years; the sales dates are shown in the scans.
The marks on the last one are hardly visible but the description states that they are there.
Please cf.
http://www.swordforum.com/forums/sho...on-Makers-Mark
http://www.google.de/imgres?q=half+m...42&tx=16&ty=68
http://www.vikingsword.com/vb/showthread.php?t=14266
I should say that the experts on the Ethnographic section could tell you more on this topic.
Best,
Michael