The blood and fluids that make up the human body are on the whole liquid crystals. Water at the heart of the living biological body is largely composed of liquid crystals (Patrick & Gael Flanagan, Elixir of the Ageless, Flagstaff, Arizona). Also among certain very enlightened people it is said that one can find crystals just under the skull! Crystals are amplifiers and transformers of energy. The least thought or gesture is immediately enlarged by the crystal, therefore it is so important that anyone working with crystals needs to work on purifying and controlling themself and mastering their ego before they work on others with crystals. Never forget that a crystal is a tool and it is the person who holds it and channels their will to heal into it. Crystals are living beings and need to be treated with care and respect. Once a good relationship has been built with a 'working' crystal, it will be a great friend who will work wholeheartedly with you.
Remember, the first crystal you need to work on is yourself!