Iron meteorite, 25 tons

At www.skyandtelescope.com/news/126009563.html there is news of a huge iron meteorite in the remote Altai mountains, on July 16th (2011). It has an estimated mass of 25 tones and is partly buried beneath a large slab of granite. This means both rocks have probably moved – and as it lies in a glacial valley the culprit is obvious. The question is how old is it, is it part of a larger cosmic object, and where might the other bits lie?