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. All of the organic matter becomes replaced by minerals, while much of the original structure such as tree rings in retained. For this to happen the wood needs to be buried in an environment both low in oxygen (preventing decomposition) and with flowing, mineral-laden water. The coloration is due to the various minerals that are present during fossilization. For example red colors are due to iron compounds, greens due to copper, etc.

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 higher concentration of impurities mixed with silica/quartz. Like agate it may form in a wide 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.