ARE CRYSTALS AND QUARTZ CRYSTALS THE SAME THING?
Nope. They all get lumped together all the time, but any mineral that crystallizes is a "crystal." For instance, technically Obsidian isn't a crystal since it forms too fast to crystallize - it's really volcanic glass. But it gets filed under Crystal all the time.
OKAY, SO WHAT IS A QUARTZ CRYSTAL?
Glad you asked. A quartz crystal is a solid material made up of silicon dioxide (silicon and oxygen) with a chemical formula of SiO2 and belongs to the hexagonal crystal system. Many quartz crystals have inclusions of other minerals, but their chemical formula remains SiO2. Rose Quartz, Amethyst, Citrine, Agate, Tiger's Eye - all are varieties of quartz crystal, even though it's obvious they also contain other minerals.
WHAT IS A "CLEAR" QUARTZ CRYSTAL?
What is called clear quartz crystal in the books may not actually look clear at all. Clear quartz crystals often look snowy or milky - caused by inclusions of water, gases, and air trapped inside - and can even have visible inclusions of other minerals, like Rutile and Tourmaline. Perfectly clear natural quartz is getting harder and harder to come by as the sources get mined out - which translates to higher prices.
DO CRYSTALS NEED SPECIAL CARE?
Yep. One of the most important things to know is that they may be hard, but they're fragile. Since many of them often have inclusions of air or gases you can't see, they should never be left in direct sunlight, put in a freezer, soaked in ice or scalding water, even though some sources recommend these methods for cleansing and recharging. The water and gases in the stone will heat/freeze before the surrounding crystal, and can crack or break apart. And crystal left in direct sunlight can cause a fire in a fairly short time. They're even sensitive to fluorescent lighting, which can damage their internal structures. In general, just remember how old these guys are, respect that, and use your common sense.
SO HOW DO THEY DO WHAT THEY DO?
There's no short, sweet answer to that. But in a great oversimplification -- the energy radiating out from any crystal automatically resonates at the quantum level in harmony with human (and other) frequencies. And since virtually everything in this dimension has its own frequencies, crystals can act as satellite receivers and transmitters, transducers, networks, storage modules, and information chips. So when you hold a crystal it begins automatically to vibrate in a frequency that is in harmony with your physical body as it is at that moment, and this harmonization does include your mind. But the full story of "how" is really a quantum physics lesson, or two....
WHEN I USE A STONE, DOES IT MAKE A DIFFERENCE HOW IT FORMED?
Well, yeah. And not just as a point of interest. If you're working with minerals to do a specialized task or program, how it was created and what its mineral content is can be very important, and useful. You want to pick the best tool for the job, after all. If a mineral was formed under tremendous pressure or heat you wouldn't want to use it to get a restful night's sleep for instance. But it would be great for that next big meeting where you have to slug it out.
ARE THERE POTENTIAL SIDE EFFECTS FROM HANGING WITH MINERALS?
For some of us, yes. If you like to wear them as much as we do, it's probably best to not wear more than five at any one time, which should cut down on potential side effects. And sometimes the frequencies of stones can interfere with or change each other - not to mention you.
WHAT ARE SOME SIDE EFFECTS?
You may get unaccountably angry, anxious, depressed
You might experience a sensation similar to an ice cream headache
Body temperatures may fluctuate
You might feel slightly light headed or dizzy
Might feel a little queasy
Some people experience a mild prickling in their hands or feet
All this is usually just from receiving too much, or too many kinds of, energy too fast.
WHAT SHOULD I DO IF ANY OF THIS HAPPENS TO ME?
Simply move out of the range of the minerals, at least three feet away. Some people take a shower to quickly reset their natural default frequencies. We personally know people who can't walk into a mineral store because of this very problem - terrible thing when you love stones. Since most of the side effects are just caused by receiving too much energy too fast, just back up a little and use smaller versions of the crystal till you can adjust and get smaller doses, one stone at a time.