Hey Swayne...
We are not to far away from each other, its gold country up here as well. I am in NE Washington state.. Kettle Falls to be specific. I think we are around 80ish miles from Spokane. Have you looked to see if there is any books on local history for your area? I know this does not answer your question about gold coins, I think thats a good question and I am hopefully that someone will have the answer.
I am really into prospecting as well as detecting, I just got my etrac about a week ago also. I am pretty much brand new to the hobby
A year or so ago when I really got into prospecting, local history really started to interest me. Now its more like an infatuation. The local history books for here are just an awesome way to compliment anyone that is into metal detecting. For an example, there is a field that I drive by 2x a day when I go into town. Come to find out, this field was a fort about 150 years ago. There is a big rock outcropping... Its always been interesting to look at.. On Saturday I learned that the big hole in the rock was from a cannon. But the indians believed this rock to be sacred. I would of never known this if it were not for local history books.
I know that a lot of settlers back in the day traveled between my neck of the woods and yours. There are tons and tons of stories of treasure that is forever buried in the ground between here and there.