Monica Marks’ ‘Amish Rock of Ages’, Good Free Kindle Christian Mystery Book, Deals Authors, Promote Your Book to 4 Million Readers. Become A Bestselling Author. Free Kindle Books – Christian Mystery *Amish Rock of Ages by Monica Marks. Price: Free. Genre: Christian Mystery, Suspense, Religious. Rated: 5 stars on 4 Reviews. 186 pages. ASIN: B085HHN8P9.