This listing is for the exact specimen pictured.
WHAT IS IT
Agates are rocks consisting of microcrystalline quartz called chalcedony. They are typically formed in pockets within cooled lava. As water flows though the lava, the pores in the cavities— called vesicles—act as tiny filters which catch silica particles that were in the water. As these particles accumulate, various silica- based minerals can be deposited to create colorful bands in the rock which can be seen whenever the rock is cut open.