Need Help with my 96 noen

Ok so i was drivng my car and it had been knocking alot that day. I stoped for a red light and upon accelerating, I heard a loud BOOM. I was not happy. I haven't taken to anybody yet but I have gotton advice froma few people. Now I believe the issue to be the head and as a result, my fan and radiator. I found long metal parts that im 90% sure ar pieces of the head (they are very flat and shiny on one side and painted black on the other) and I am wondering how much it is going to cost me to get this fixed. If you can help me out please let me know. Thanks and if you need more information to determine the problem then please contact me via email at pimpusa1023@yahoo.com and actually that would be the best place to give me any advice as well. Thanks

The head itself is all silver from the aluminum. Black pieces are probably from the valve cover. Can you get any pics of the engine?