Clear Quartz
There are many books and web sites listing the properties of various minerals, but not so much is written about quartz. So here follows a few thoughts that may be of interest.
The Master Healer
Clear quartz, often referred to as the Master Healer, is naturally six sided and is more commonly translucent. Its chemical formula is SiO2, that is, it is composed from silica and oxygen. If you were only ever going to have one crystal, then quartz could be your best choice.
Whilst all quartz is able to hold and give off energy, not all is able to direct or focus it. This is due to its molecular structure that varies according to where the crystal formed. Madagascan quartz, for instance, is neither appropriate for healing nor for use by the electronics industry, because the internal structure is inconsistent and hence non-directional, but it does make very beautiful and affordable spheres which are perfect for bathing a space in energy.
Piezoelectric
Good healing quartz is piezoelectric: it can convert movement into electricity, or electricity into movement. It converts one form of energy into another. Exerting strong pressure upon a quartz crystal will produce a spark (the principal used in many gas lighters) whereas applying a voltage across the crystal produces a steady pulsing. It is for this reason that this kind of quartz is used in the electronics industry as well as for healing. Because quartz pulsates at a constant rate, it is possible to use it for clocks and guidance systems, indeed the very heart of every computer and digital device on the planet, and also for balancing the human energy body.
On an elemental level we are partly made of the same stuff as quartz, therefore it is compatible with our auric field and unwanted energy can be converted into a more useful energy.
Generally speaking clear quartz crystals take in energy from their sides and bases, and give out energy from their points. For this reason it is important to choose crystals with undamaged points.