The Secret of Hermit's Peak by Dan Scott (Bret King Mystery, Very good, 1960, HC, 181 pages, Grosset & Dunlap)

In very good condition: cover has some wear; pages have very light wear.

Nothing upsets Rusty King more than the loss of one of his prized colts. A rogue mountain lion is believed to be the culprit, and the Rimrockers attempt to track the lion to its lair on Desolation Peak. The journey proves to be too perilous for them to complete on their first attempt. Even worse, the hermit, Ol' Whiskers, threatens to shoot them if they continue searching near the peak.
As the story goes, Ol' Whiskers has a hidden mine full of gold, and he guards it with his life. A couple of unsavory men ride onto the scene, camping out near the peak. Each time the boys try to track the lion, they must contend with the men who use potentially deadly force to keep them away. The men are searching for Ol' Whiskers' gold, and they will stop at nothing to find it.

The Secret of Hermit's Peak
Too late, the boys realize the grave danger that threatens both Ol' Whiskers and them. How the Rimrockers face their foes and help Ol' Whiskers makes for a thrilling adventure.