Crystals and Gemstones

Not sure where to post this but here goes...

I would like to know some information regarding crystals and gemstones and their metaphysical properties.

Is it more effective to carry around one stone with you all the time or to carry a variety of stones in a sack or something?

How long should you leave them out in the Sun for to charge/energize them?

And if I posted some pictures of the ones I have could you guys identify them for me?

Oh, and what is the most effective way to merge or absorb the energies that they give off?