Why and How to Cleanse your Crystals and Gemstones - Pinny sez: I can't vouch for all of these, but some are good. Best is water bath, then sunlight to charge, or leave for a day or so on a citrine cluster (not amethyst). Burying in earth for a day or so is good, too.
Healing Crystals - recently given an amethyst and have been blown away - read what it could do for me AFTER I had it a few days and am in no doubt about it's healing power. Love my amethyst and now researching more!
Smokey Quartz Sphere~grounding and stabilizing, relieves stress, fear, jealousy, anger and other negative emotions by transforming them into positive energies; brings prosperity, good luck, and protection
Crystals for House Protection...For general house protection from negative energies, I highly recommend Black Tourmaline. It is among one of the most protective and grounding crystals. It protects against all forms of negative energies Selenite is protective and brings about a calming, angelic quality into the home. It promotes a peaceful atmosphere. Think of Black Tourmaline as being a protective shield and Selenite the guardian angels
smoky quartz - Smoky Quartz is almost a default crystal in any crystal layout. It is grounding, protective and can transform negative energy into positive energy. As one friend put it to me, Smoky Quartz is good for humans, because we are currently quite murky beings ourselves!