cut and polished agate with green and white colors

agate background banded beauty block book brown chalcedony closeup color complimentary cross crystalized crystalline cut decorative design exterior form geology green halves ingredient large lines luster marbled micro mineralogy natural nature opaque organic outer pattern piece polished quartz rough sample semi-precious semiprecious shiny smooth specimen split stone streaking structure surface table text texture textured together top two type variable view waxy-flat white wooden