Dream Mine — Dave Stone

There's gold in them thar hills! At least that's what folks say. An ancient mine lies in the foothills above town. That's harmless enough, I guess, until one day strangers from another place decide they want the treasure that's hidden within -- but can it be found?
An angel guards the way. That too is what folks say, but where there's a will there's a way. A woman is found, a person of unsavory standing. She's a sorceress with mystical powers who possesses the key to unearth the gold.
Two boys, minding their own business, are drawn into this dubious adventure when one of their classmates, a girl named Skye, is kidnapped and held in the mine along with her grandpa.
Can the boys save them? Only time will tell. Up against spirits, weaponry, and long dark shafts, the boys do what they can, but who will help them? Only time will tell.