Raurg bones are associated with the Prayer skill, giving 96 prayer experience when buried.
They are obtained from Zogre coffins, which will often break lockpicks and decrease players' thieving abilities upon opening using thieving methods. They can also be obtained by looting a zombie impling jar. (Zombie impling require level 87 hunter to catch.) These bones are impractical to train prayer with, as they are significantly more expensive than Frost dragon bones, therefore it is recommended to sell raurg, fayrg, and ourg bones accumulated from ogre coffins.
The price of raurg bones significantly increased on 19 September2012, due to the release of the challenge system.
Training from level 1 to level 99 Prayer by only burying raurg bones would cost 8,616,344,960 coins, assuming no experience boosts are used. Training to a total of 200m experience would cost 132,208,375,640 coins. This method is currently the worst method in the entire game of training prayer cost-wise.