Alison Krauss and Robert Plant 'Raising Sand' (Photos)

and, in a collaboration album released last October, received critical acclaim for Raising Sand. They credit much of the success to, who produced the album and gave it its somewhat haunting musical style. He plays guitar on 10 of the 13 tracks.

The folk based album was nominated in July 2008 for the Mercury Prize, awarded for best UK album. The Pair toured the UK, Europe and the U.S. beginning in May 2008 and culminating with a final performance on October 5, 2008.

Krauss, 37, is a blue grass country singer and fiddle player. Plant, 60, is an English rocker singer and song writer who played lead vocals for Led Zeppelin. In September 2008 they won several prestigious awards at the 7th Annual Americana Music Association Awards in Nashville. They won Duo-Group of the Year and Album of the Year for Raising Sand.

Katie Couric featured the pair on CBS Sunday Morning on October 12, 2008 in a 10 minute segment. Between them they have sold 30 million records. Both hinted that they may do another album with T-Bone Burnett. Alison said she'll be interested to see what Burnett comes up with next.

Check out our photo gallery below. Also check out their recent performance of Hardly Strictly Bluegrass in SF plus a look at the making of Raising Sand.