I'm going to tell you how to make Kryptonite with a piece of quartz (found at the beach) and a pair of green LED
Step 1: Piece of worn out quartz
Step 3: Drill the hole on it
PS : You can see on my thumb my own coin ring made from here
Step 5: Weld the wires
Step 7: Set the power ON
And now Superman beware of you i've got my own Kryptonite.
This instructable is my first one, excuse me if my english is too not so good I'm a french people (still sorry ;-) ) from New Caledonia .