Carrying crystals, a few questions.

If you are using crystal for your own and have one goal then there is no problem in keeping them together. But you should be sure that the soft crystals do not get the scratch from the hard one.
It is especially important in the case of crystals to clean them before before you begin meditation work with them. Even if they feel ok, so that’s your own energy you are working with. Their strong electromagnetic fields mean they can easily collect and store the energy. There are various methods to cleanse crystals are flowing water, sunlight or moonlight, salt, energy etc. After cleansing you can program the crystals. Human thought directed into the crystal can program it up very nicely, quickly, and easily. Hold the crystal in your hand and think about what you want the crystal to help you with.