As Metallica prepare for their Orion Music + More Festival and upcoming 3D concert film, the band is also busy working on a new album. One could say that Metallica have a ton of songs on the table, as frontman James Hetfield revealed that the band has collected 846 different riffs.

In a new interview with Rolling Stone, its been revealed that fans have nearly a thousand reasons to look forward to a new Metallica record, as Hetfield speaks about the writing process. "I only have 846 riffs," says Hetfield. "In iTunes, you can see how many things you've got. And that does not include the soundchecks, the stuff we goof around with here. You plug in an amp. Suddenly it makes you feel good — you come up with a riff. 'Dude, did you get that?' You can't get away from being recorded here."

Hetfield continues, "But Lars, the hoarder of Metallica, is obsessed with revisiting every stone, turning it over: 'That could be great!' Yeah, it could all be great. But I've got a new one right now. That's the Catch-22. You've got a riff from five years on tour that's amazing. Do I still feel it? Don't worry. Something better will show up."

Bassist Rob Trujillo brought even more insight into the ideas which will have fans swaying to Metallica's beat. "I have about 20 ideas that I feel really good about, whereas on 'Death Magnetic' I had one or two," adds Trujillo. "But one of them ended up being 'Suicide and Redemption'. Hetfield — he's a writing machine. Kirk has over 300 ideas. There's so much stuff from the tuning-room jams, from all those years of touring."

Full interviews with each member of Metallica are now available in the latest 'Big Issue' of Rolling Stone magazine.