Well, this is for two reasons. One is due to the fact that this item is worth a staggering 16,555,304 gold. However, this is arguably due to the other reason. This item is a key component which when combined with an item called the helm of Neitiznot, can create the Neitiznot faceguard. This is a very desirable item as it has the highest strength bonus of any helm within the game. This helmet is in theory worth 550,000 gold. However, this is an unreadable item which explains why the component, the Basilisk Jaw has such a high price tag. It is also worth noting that this helm requires 70 defense to wear, requires that the player complete The Fremennik Exiles quest to create and the player will only be able to trigger this crafting ability by speaking to Olaf the Bard when the player has a Basilisk’s Jaw in their inventory.