Jogres are found on Karamja. Kill them to obtain jogre bones. Also found in cages at Ardougne Zoo. Bones will need to be telegrabbed from the cages.
Uses:
Burying yields 15 prayer experience.
Putting these into a furnace yields Burnt jogre bones and 25 Cooking XP.
Lighting these on fire with a tinderbox yields Burnt jogre bones and 90 Firemaking XP.