6.9" Green Jasper Replaced Petrified Wood Stand-up - Oregon

Petrified wood is the name given to wood that has been turned into stone (fossilized) through the process of permineralization. In this process, all of the organic matter becomes replaced by minerals, while much of the original structure, such as tree rings, is retained. For this to happen, the wood needs to be buried in an environment low in oxygen to prevent decomposition and with flowing, mineral-laden water, so minerals may replace structures. The coloration is caused by various minerals that present in that water during fossilization. For example, red colors are due to iron compounds, greens due to copper, and so on.

Jasper is a term that can be applied to an opaque variety of chalcedony. The opaqueness is due to a higher concentration of impurities mixed with silica/quartz compared to other varieties of silica, such as quartz or agates. Like agate it may form in a wide variety of colors, and is often multi-colored. In most cases, jasper forms 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, but other factors can play a role in the color of what is now considered a jasper.