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Almost every creature you would expect to have a skeleton usually drops bones. You can pick them up and bury them by clicking on them to gain 4 experience for your Prayer skill. Some stronger monsters drop bones that are worth more experience.

People who are not developing their Prayer skill will often leave bones behind, so be sure to pick them up and bury them whenever you see them.

Name	Experience gained from burying	Selling price	Dropped by	Notes	Members only
Bones	4.5	10-50	Almost every NPC and wearker monsters.	These bones look very small and most monsters drop them. Some random events also leave bones.	No
Burnt Bones	4.5	10-50	N/A	These bones are found in the wilderness in the northeast near the Greater Demons. They are not rare and give no more experience than regular bones.	No
Monkey Bones	5	10-50	Monkeys.	These bones are dropped by monkeys around the volcano on Karamja.	No
Bat Bones	5.33		Giant Bats.		Yes
Big Bones	15	150-450	All giants.	These are the highest bones that free players can bury.	No
Jogre Bones	15		Jogres.	These give as much experience as big bones.	Yes
Baby Dragon Bones	30		Red and Blue Baby Dragons.		Yes
Skeletal Wyvern Bones	50		Skeletal Wyverns.		Yes
Dragon Bones	72	1600-25000	All dragons.		Yes
Dagganoth Bones	125		Dagannoth Kings.		Yes