The Amethyst Hook is a tool that behaves similarly to the Grappling Hook, only it is purple-colored and has a slightly shorter range. It is one of the weakest hooks. It requires 15 Amethyst to craft at an Iron Anvil.
Due to Amethysts being so common, it is most likely the first Gem Hook the player will acquire.
As with all the hooks grappling onto a door and opening it sends you hurling forward with great speed.