This one was sold to me as natural agate from Tibet.
The more I look at it , the more I feel this bead has been coloured since the matrix is slightly more bluish than the rest.

The question is for all three bead sets:
- are they all the same stone type?
- what are they exactly, if agate is there a specific name for this type of agate.
- Am I right to think that 1 & 2 are natural and nr 3 is coloured.

Thank you!!