Chewed bones are obtained exclusively as a drop from mithril dragons in the Ancient Cavern. No other monsters in the Ancient Cavern will drop chewed bones, and looting the skeletons won't give chewed bones either (only mangled bones).
When these bones are put on a pyre ship and burnt (requires a tinderbox, axe and any type of non-pyre log), they will summon a Barbarian spirit, who may thank you for putting his soul to rest with an item. The reward may be a dragon full helmet, various potions, runes or projectile ammunition. Many players will attempt killing mithril dragons in the hopes of obtaining a dragon full helmet drop; if unsuccessful, they can take any gained chewed bones to be burned in a pyre ship for another chance at gaining a dragon full helmet, however the chances of that are fairly rare. Note that using higher level logs does NOT increase chances of receiving a dragon full helm.
Burning chewed bones via a pyre ship provides an experience bonus (300%) to any bones buried for the next 5 bones. You will receive a message saying, "You gain extra prayer experience as the ancestral barbarian spirits watch over you." This bonus accumulates. Burning 2 chewed bones consecutively provides a bonus for burying twice as many bones as burning one chewed bone. Dying does not remove the accumulation of bonuses.
Dropping monsters[]
Monster Combat level Quantity Rarity Mithril dragon 304 1 Uncommon (1/42)

An Ancient Barbarian Spirit being laid to rest
Rewards[]
Item Quantity Rarity GE market price Death rune 8–15 Common 1,624–3,045 Blood rune 4–27 Common 1,468–9,909 Diamond 2 Uncommon 3,782 Big bones 10 Rare 2,620 Dragon full helm 1 Rare (1/250) 40,474,531
Potions[]
Item Quantity Rarity GE market price Prayer mix(1) 1 Common 3,040 Prayer mix(2) 1 Common 5,608 Ranarr potion (unf)(noted) 2 Common 15,736 Anti-poison supermix(1) 1 Common 284 Super str. mix(1) 1 Common 942 Superattack mix(1) 1 Uncommon 1,254 Superattack mix(2) 1 Uncommon 322 Super def. mix(1) 1 Uncommon 356 Super def. mix(2) 1 Uncommon 356 Antifire mix(1) 1 Uncommon 455 Antifire mix(2) 1 Uncommon 440 Fishing mix(2) 1 Uncommon 125
Ammunition[]
Item Quantity Rarity GE market price Mith grapple 1; 2 Common 1,055–2,110 Silver bolts 5 Common 30 Rune arrow 10 Common 700 Rune dart(p) 20 Common 21,960 Rune knife 20 Uncommon 6,260 Adamant knife 20 Uncommon 7,640 Runite bolts 10 Uncommon 4,030
Standard bones | |
Draconic bones |
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Monkey bones |
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Ogre bones |
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Enriched bones | |
Special bones |
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