In-game pickup not moving towards player after being collected

var scoreValue : int = 1;

private var target : GameObject;

private var pickedUp = false;

function Start () { target = GameObject.FindGameObjectWithTag("Player"); }

function OnTriggerEnter (other : Collider) { // Make it go towards the penguin and disappear pickedUp = true; Debug.Log("Gem collected!"); }

function Update () {

 if (pickedUp)
 {
     // Move the gem towards the player
     transform.position = transform.position - target.rigidbody.position * Time.deltaTime;
     Debug.Log("Moving gem to player...");
     //Remove from game environment after being collected
     //TODO: Add scoring system
     if (transform.position == target.rigidbody.position)
     {
         Destroy(this);
         Debug.Log("Add score");
         //TODO: take scoreValue and add it to the player's score
     }
 }