A strong Runecrafting urn is used with the Runecrafting skill to help gain experience. It will collect rune remnants while crafting runes that require up to and including level 77 Runecrafting. It can also be used while siphoning in Runespan. Once the strong Runecrafting urn is full, it becomes a strong Runecrafting urn (full) and can be teleported to Ernie for 1,000 Runecrafting experience (1,250 with an urn enhancer). You may only own 10 full urns in your inventory/bank at once, if you have 10 full urns a new one will not be started.