The following verses are the last time that head is mentioned. There is no indication of what became of it.
1 Samuel 17:54 And David took the head of the Philistine, and brought it to Jerusalem, and his weapons, he put in his tent. 55 And when Saul saw David going out toward the Philistine, he said to Abner, the general of his army, "Whose son is this youth, Abner?" And Abner said, "By your life, O King, I know not." 56 And the king said, "You ask whose son this youth is." 57 And as David returned from slaying the Philistine, Abner called him, and brought him before Saul, and the Philistine's head was in his hand.
bob>Verse 54 says David took the head back to Jerusalem, which is what I was pointing out. The question is, what did he do with it. Some Jews, as I am told, understand David buried the head in a small mound, but the mound grew and became Golgotha, which is to mean the skull, a mount in Jerusalem, is this what you understand?