In the stones selecting, which you are planning using for meditation, thus attention and on the goal getting by meditation.

Stones are orange and red as interesting, clear, attention raising and needing active meditation, as good for those,who are tire faster, sleeping, loosing forces, as they are meditating for energy and attention keeping.
Golden and yellow supporting our sense meditation, and helping for deciding in problems, as in indecision, they are leading your mind in a big clearness.Pink stones are teaching to love to itself, and close, calming aggression, giving tolerance and softness/Green stones are self curing, caring for immunity, are in big stress they are matching for meditation.Blue are calming, deep meditating, as good for those who is hard turn off of hard life.Violet are harmonizing minds and needing in the soul developing, and who is hard attending in minds, who can not ability doing this. White stones are in mind helping for self understanding.Black and brown are stay you on earth, stabilizing caring, who is not attending, or hard doing this, and who cannot returning of meditation. Select a stone matching for you, as intuitively, as to know a better an effect of this stone.