15.5" Stunning, Polished Jasper Stand-up - Marston Ranch, Oregon

This is an absolutely stunning, 15.5" wide slab of polished jasper from the Marston Ranch near Ashwood, Oregon. The quality of the polishing work on this brilliant piece is exceptional with no null spots or scuff marks. There is some debate about whether this material is jasper replaced petrified wood, or jasper formed from some other mechanism. It looks like some sort of brecciated jasper with pockets of agate to me.

The piece weighs just over 13 lbs and has been cut flat on one edge for presentation purposes.

Jasper is a term that can be applied to an opaque variety of chalcedony (light does not pass through it) The opaqueness is due to a much larger amount of impurities mixed with silica/quartz. Like agate it may form in a huge variety of colors, and is often multi-colored. In most cases, jasper will occur when silica-rich fluids permeate throughout a soft sediment or volcanic debris deposit. The fluids then crystallize around the particles/impurities, resulting in a cementation process. Most often, the impurities present determine the coloration of the deposit following solidification, however other factors can play a role in the color of what is now considered a jasper.

Chalcedony var. Jasper
Marston Ranch, Ashwood, Oregon
15.5 x 7.3", 1.7" thick