A summoning focus is an item that can be made by combining one of each type of item produced by a crafting catalyst, namely a leather case, gem focus and a metal setting. Making 1 focus gives the player 10 bonus experience in Crafting (this is unaffected by bonus experience already available or double XP weekends). A whole stack can be made at once. It gives an extra 20% Summoning experience when making pouches at an obelisk. One focus is needed for each pouch made.
Crafting catalyst was removed from Treasure Hunter on 24 November 2014.
On the 26 November 2014, Mod Obeith stated in a reply to the questioning of the removal of Crafting Catalyst, leather case, gem focus and metal setting from Runescape completely "Crafting Catalysts have been taken off of TH but the items won from there will not be removed. Therefore unused catalysts, uncombined focuses parts and the completed focuses will not be removed so you are free to keep them and use them when you want."