Wearing crystals help raise the vibration of the human body and reconnect you back to earth. This is essential to us as humans because the higher our vibration the easier it is to broadcast a powerful energy signature (transmit information) and receive higher vibrating energies (receive higher information for bio download).
Most human-beings are vibrating at very low frequencies, especially since the introduction of cell phones which we carry on our person everyday. All human-beings have different millivolt ranges in their nervous system. Our nervous system runs positive and negative ions throughout our entire body.
The state of health you're in can be measured by millivolts. The average person at the average state of consciousness ranges between 30-100 mv (millivolts) 1/1000th of a volt. A person who suffer from severe depression will usually measure between 5-9 mv.
The point of wearing crystals is to raise the human body voltage (which is the electricity in our nervous system) to higher levels. This will make it easier for us to project our thoughts to cooperatively effect our reality.
Or bodies are like a radio transmitter/receiver, if you don't have enough power in your nervous system and you are trying to send thoughts out into the universe to effect your reality. The chances of you manifesting your reality the way you want it to be are going to be much lower.
The heart center produces the strongest signal out of all the energy signals of the body. If you intend to send out a signal to attract a response with a damaged central power system, it will be weak a signal and a weak signal can not be picked up.