Crystal knife

The crystal knife is a degradable knife that is made by Crystal Singing with a crystal tool seed and 150 harmonic dust. This requires 80 Smithing and gives 300 Smithing experience. Alternatively, you can pay Ilfeen, Eluned, Islwyn or Rhodri Dail 1,500 - 7,500 coins to turn a crystal tool seed into a crystal knife, without any harmonic dust or 80 Smithing.

The knife has two effects: it gives a 5% chance of getting double arrow shafts from fletching Logs, and it gives a 5% chance of giving a strung bow instead of an unstrung bow when Fletching unstrung bows. Experience for stringing the bow is given as normal and it will still count towards any daily challenges. The knife will consume 3.57% charge per activation, or 1.78% in Prifddinas, thus lasting 28 or 56 times before degrading back to a crystal tool seed. The tool seed can be recharged by Ilfeen, Eluned, Islwyn or Rhodri Dail for a cost that starts at 7,500 coins but decreases by 1,500 every enchant, to a minimum of 1,500 coins. You can also talk to Ilfeen, Eluned, Islwyn or Rhodri Dail if you want to turn your knife back into a seed.

Like the other crystal tools, the knife doubles the chance of getting Fletching strange rocks from Shattered Heart.