Agate slice on black base

Natural black and white agate slice from Brazil, on black base. And before being this stone, it was an air bubble in the cooled lava of a volcano. The lava has become basalt: a porous rock, and this chamber has been successively filled, over millennia, with water with dissolved minerals. Like manganese oxide that gave these black lines all around and these nuclei in the middle of quartz crystals. Each flood brought a new crystallization... When the light passes through it as in photo 5, it takes an incredible depth. One could imagine an aerial view of a snow-covered forest with very black pine trees. (in any case, that’s what I imagine...)