Well, I have listened to lots of extreme metal, and there have been some pretty heavy stuff I have listened to. This isn't an official answer, but Nile are pretty heavy. And although I'm not a real fan of theirs, latter Behemoth has some heavy music as well. Sunn O))) and Electric Wizard also have an aura of heaviness about them. They are very heavy bands, but not in the same way that Nile and Behemoth are.
Bismuth.
" has the symbol Bi and atomic number 83. This trivalent poor metal chemically resembles arsenic and antimony. Bismuth is heavy and brittle; it has a silvery white color with a pink tinge owing to the surface oxide."
It's a heavy metal element. ;P
Most Vulgar Lyrics:
Most Gothicly Dark:
Heaviest Death:
Heaviest Brazilian Death:
no disrepect meant to Sepultura,
Heaviest 3-peice female: Mythic
Pablo
" has the symbol Bi and atomic number 83. This trivalent poor metal chemically resembles arsenic and antimony. Bismuth is heavy and brittle; it has a silvery white color with a pink tinge owing to the surface oxide."
It's a heavy metal element. ;P