One of a kind, huge silver bearing Sowbelly Agate polished display specimen. For Sale

This is, as far as I know, a one of a kind specimen of this agate from the old silver mine dumps at Crede Colorado. Most of these agates are sliced into cabbing slabs. This one I face ground and polished by hand (a big job) front, back, and two ends. One end is left natural. Not only is this a rare and beautiful piece, which I could not do justice to in the photo though I tried several lighting setups, it is noteworthy Americana of the old west. This agate seam, being resistant to weathering, was the marker the old prospectors looked for. Wherever they saw pieces of this agate on the ground, they knew the silver ore was nearby. This agate seam, called \"sowbelly\" or sometimes \"amethyst\" can still be seen in the walls of the old mines in videos online. The dark plumes are silver oxides or sulfides.
The piece is roughly 10\"x10\"x1.5\" and weighs about 12 lbs.
It will come with the acrylic stand, and walnut riser at no additional cost if requested.