Beautiful fairly rare find from Peru! These blue chalcedony pieces have a stunning naturally blue coloring on a matrix stone.  Some of the formations are botryoidal and some are more tabular.  One of these even shimmers (like grape agate does).  Some also have some dendritic lines on them.  Peruvian blue chalcedony might just be one of my new favorites!  Blue is one of the hardest colors to photograph (so weird), it tends to wash it out, but believe me when I say these are amazzzzzing.