The album consisted of 11 tracks, all of which were stemmed from themes of coal mining in the Appalachian region of the United States.

A majority of the album's material were covers of songs previously recorded by other singer-songwriters such as Hazel Dickens and Jean Ritchie.

She has said that she was expecting a set of stories in the songs she covered on this album, but instead found a connection to her miner ancestors.

Most of the album's material came from the pen of three writers: Hazel Dickens, Jean Ritchie and Billy Ed Wheeler.

"[7] In a more mixed review, Grant Alden wrote in No Depression that Coal was "a complicated conversation, one she seeks gently to engage all of us in," and praised her cover of "Red-Winged Black Bird" as the album's best song.

He also criticized her treatment of "Coming of the Roads" as "prosaic" and wrote that she added nothing to the Merle Travis song "Dark as a Dungeon".

[10] Jonathan Keefe of Slant Magazine gave the album 4.5 out of five stars, calling it "her most ambitious work".

"[6] Coal was released on April 1, 2008 on Captain Potato Records in conjunction with the Thirty Tigers label.

[5] It spent four weeks on the American Billboard Top Country Albums chart, peaking at number 64 on April 19, 2008.