Coldplay star Chris Martin almost backed out of his collaboration with SHAWN 'JAY-Z' CARTER because the melodies he conjured up sounded too good to share The 99 PROBLEMS rapper invited Martin to write music for his comeback album Kingdom Come and experienced a horrible moment when he believed Martin would back out and use the compositions on the next Coldplay album He says, "Chris Martin sent me these wonderful chords one day and he said he knew they were good because he almost didn't tell me about them "He was gonna keep them for himself For one second he said, 'I'm not sending this to him '"