VIDEO : Prince Vaults Open With Jazzy 'Piano & A Microphone'

NEW YORK (Reuters) - A nine-track album from Prince?s vast vault of unreleased material goes on sale on Friday, along with a new video highlighting gun violence. REUTERS/Chris Pizzello/File Photo ?Piano & A Microphone? is compiled from a 1983 home studio cassette of the late musician playing jazz piano versions of some of his own songs and those of others, record company Warner Bros. said on Thursday. Prince in 2015 performed at a Rally 4 Peace concert in Baltimore following the death of Freddie Gray from injuries suffered in police custody.