This listing is for this exact high energy clear quartz vogal wand.
weight/ 72 grams 
size/ 3 inches 
The purpose of a Vogel crystal is to amplify and cohere (gather) the thought and energy that you desire to focus into your body/mind or that of another person.
 
Amplification we can understand, but coherence is a more obscure concept in physics terms. 
 
To simplify, when applied to the physics of light, coherence is the condensing of the light wave/particles into ultimately a laser beam. As example, if you take ordinary light and condense it or make it coherent, you end up with is a laser beam.