Make sure we cannot place down artifacts...

src/plugin.yml

@@ -1,6 +1,6 @@
 name: TwosideKeeper
 main: sig.plugin.TwosideKeeper.TwosideKeeper
-version: 3.4.0
+version: 3.4.0a
 commands:
    money:
       description: Tells the player the amount of money they are holding.

src/sig/plugin/TwosideKeeper/TwosideKeeper.java

@@ -1533,6 +1533,10 @@ public class TwosideKeeper extends JavaPlugin implements Listener {
     		//This is an item cube.
     		ev.setCancelled(true);
     	}
+    	
+    	if (Artifact.isArtifact(ev.getItemInHand())) {
+    		ev.setCancelled(true);
+    	}
     }
     
     @EventHandler(priority=EventPriority.LOW)