Sequatchie,
Your posted A. Lawing rifle with a brass colored guard was described as "brass overlay." Based on similar guards made in southeastern KY just above the TN line, guards like this were actually made out of three strips of solid brass and riveted together to make a TN style guard. I can see one rivet on the back of your bow, but your guard may have also been soldered since joints are smoothed so well. In KY it is easy to see the three pieces used to construct the guard, and the rivets holding them together.
One KY maker, William Hall in Floyd Co., actually cast a couple TN style guards that look like this... that had to be tough!
Shelby Gallien