Aluminum Base
From Pixelmon Wiki
An aluminium base is created by placing an aluminium disc on an anvil (by right-clicking the anvil when holding a disc), then using a hammer (holding left-click) on the anvil. Eventually, the disc will turn into an aluminium base, which can be re-obtained either by continuing to hold left-click or by right-clicking. Aluminium bases are functionally equivalent to iron bases and can be used to make almost every type of Poké Ball.