The 'dark material' could very well be organic compounds carried there by the same things that deposited the ice: comets
More info can be found at a blog (Bad Astronomy) I trust. They have actually found some compelling evidence (it's not proof, but it's about as close as we can get without landing something there) for large amounts of ice on Mercury.
-Terry
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"so listen up boy, or pornography starring your mother will be the second worst thing to happen to you today"
TF2: Spy
More info can be found at a blog (Bad Astronomy) I trust. They have actually found some compelling evidence (it's not proof, but it's about as close as we can get without landing something there) for large amounts of ice on Mercury.
-Terry
-----
"so listen up boy, or pornography starring your mother will be the second worst thing to happen to you today"
TF2: Spy