If I may share...
I notice some basic correspondences of the Elements...
Athame- Athame, swords, etc., are usually considered Air tools, as Air is the Element of Freedom, Intellectualism, and Honesty. Notice in the Suit of Swords in Tarot, it is usually considered Air, because of the Swords represented, harsh, cutting Truth.
Pentacle- Pentacls are considered tools of the Element Earth, as Element Earth is known for Prosperity, Wisdom, Purifying... In fact many Pagans say that to purify or Bless an object, one would put their object on their Altar Pantacle, bury it in The Earth, or sprinkle salt on it.