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
When i'm walking at th beach under the cliffs i found some pieces of quartz.This quartz pieces where roll, roll and roll by the waves and they are worn out and polish.
Step 2: Chose One of Them
Chose one of the quartz pieces.
Step 3: Drill the Hole on It
With your favorite Dremel drill one or two holes to receive the green LED.
PS : You can see on my thumb my own coin ring made from here
Step 4: Glue the LED
With a hot glue gun fix the LED in the hole
Step 5: Weld the Wires
Weld the wires on the LED, personnaly I use two green LED retrain from an old computer casing. Be sure to respect the polarity of the LED (elsewhere the LED doesn't work).Glue the wire on the rock .
Step 6: Stand It
Cut a little square a "precious wood" and glue the rock on it
Step 7: Set the Power ON
I use a multiple power supply set on 3 volts to feed the LED but you can use 2 size AA battery.
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 .