I can see where the white one could be a bone fragment.
Not sure about the blue or darker one?
I looked at them with a Jewlers microscope and the one that appeared "blue" seemed to be more dark brown or black instead of blue.
I have two relics.
One is St. Francis Xavier, and it has a white center.
The other is St. Teresa of Avila, and it has a blue or dark center.
What is the significance of the two different colors.?
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