I must share the standard disclaimer that I am not a doctor and cannot give out medical advice. Crystals for healing should be used as a compliment to other therapies and not as a replacement for regular medical care.
There has been some recent research that shows that size and color does matter. Research is showing that the small flat stones will vibrate at a higher resonate frequency that large round stones. Pastel, white and clear stones have a higher frequency that darker stones. Stones with two or more elements will vibrate higher then single elements. The human body resonates at a harmonic frequency of 62-78MHz and stones with higher freq will maintain or raise the frequency if it should drop below the normal average.
A good starter book is Judy Halls Crystal Bible, as it has a ton of good info and pictures to help identify crystals.
As for a good solar plexus stone, try the bright or pale yellows. Yellow apatite, Yellow Tourmaline, Citrine, Golden topazor Golden Beryl. The yellow green stones are also a good choice.
Master Crystal Healer
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