Mystic is a city in Appanoose County, Iowa, United States.

[3] At the end of the 19th century, "the valley of Walnut Creek was one continuous mining camp, known under different names, Jerome, Diamond, Mystic, Clarkdale, Rathbun and Darby" (later known as Darbyville).

The Mystic coal seam was exposed on the surface there, and drifts were opened and abandoned over the next few decades until the hills were honeycombed with mines.

In 1858, Isaac Fuller opened a large mine in Mystic, shipping coal for domestic use in nearby Centerville.

In 1887, the Chicago, Milwaukee and St. Paul Railway built a line through Mystic, leading to an explosive growth in mining.

[4] Local Assembly 3335 of the Knights of Labor was based in Brazil and had a membership of 75 in 1884.

[9] The miners of Mystic and Brazil joined the United Mine Workers in 1898.

[12] Mystic is located in the valley of Walnut Creek, approximately four miles southwest of its confluence with the Chariton River.

According to the United States Census Bureau, the city has a total area of 2.92 square miles (7.56 km2), all land.

31.5% of all households were made up of individuals, and 12.1% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 99.15% White, 0.17% Native American, and 0.68% from two or more races.