The hallmark is 10 with a circle next to it, inside the circle there is a symbol similar to this \_o_/ under the o and the funny boat shaped symbol there is also the letter c hope this makes sense!

Gold trademarks are typically attached to company or crafter trademarked names. This means buyers can actually trace the origins of their rings or bracelets directly to their makers through the U.S. Patent and Trademark Office. In some cases, these gold trademarks, depending on the company in question and the mark itself, can help date a piece based on its estimated production time.

Gold Hallmarks World Reference Guide (http://www.jewelry-precious-metals.com/gold-hallmarks.html)

I can't find the hallmark for your watch. I have better luck finding Native American hallmarks.