Check related link.
You get charms by monster drops.
It can reset your drop rate, making you get worser drops.
Dagannoth Rex
about 30sec or 1min
The level 83 cockroach soldiers drop them on occasions in runescape, for nonmembers and members.
Ice giants have very good drops. Go to Runscape database to see monsters drops.
Those are rare drops from treasure trails.
the level 580, kree'arra.
The Kalphite Queen
Waterfiends.
Granite Armour can't be made in Runescape, it consists of monster drops and various mini-game rewards.
Im not sure about any monster that drops them in small ammounts, but the Giant Mole under Falador Park sometimes drops 1380 at a time