Dramatic pattern in this large "Tuxedo" agate cabochon.
This banded agate has been treated to cause the strong black coloring.
The white areas were unaffected by the treatment, resulting in the great contrast seen here.
Note the strong parallax effect in this stone. Parallax or shadowing in banded agates is an
optical effect produced by the regularity of alternating clear and opaque layers in the agate.
Moving the stone can give the appearance of movement across the bands. See additional images below.