How petrified wood is made

Petrified wood is actually stone that looks exactly like wood

Petrified wood is actually stone that looks exactly like wood. The detail in the stones is amazing - it looks just like wood but is much stronger and heavier. You can even see the tree rings.

Petrified wood literally means wood turned into stone. The word petrify comes from the Greek word “petro” or "rock" - Petrify means “to change organic matter into a stony concretion by encrusting or replacing its original substance with a calcareous, siliceous, or other mineral deposits.” The way wood becomes petrified is a very interesting process.

Petrified forests found today were live forests around 65 million years ago.

The process of petrifaction

The first step for wood to become petrified is that trees end up being buried by sand or volcanic ash or some other substance and therefore take a long time to rot. They are also submerged in water. Most logs subjected to these conditions would simply decompose before the petrification process began, but for some reason they don’t in certain areas.

While they are buried, water with a lot of dissolved minerals enters into the wood and deposits minerals inside the tree’s cells, taking on the exact shape of the cell. Over time, all of the cells become filled with minerals while the organic matter decomposes. The resulting stone looks exactly like the tree.

Generally only the trucks of petrified trees are found because the leaves and branches are softer so tend to decompose faster than the minerals can accumulate in the cells.


Petrified wood can be found in many different colors. What color the stones will be is dependent upon the chemicals in the soil. Petrified wood is nearly all quartz crystals, but quartz has almost no color. It can be combined with other elements to add color to the petrified wood. If you add carbon, the stone is black. If you have copper, it becomes green/blue; if you have manganese it becomes pink/orange. Iron can make it orange, red, or yellow.

Where petrified wood is found

Petrified wood can be found on every continent with trees, or every continent but Antarctica. Some places petrified wood is commonly found are: USA, Argentina, Brazil, China, Indonesia, UK, Egypt, New Zealand, Australia, and Ukraine.

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Wood turns to stone when it gets buried in sand or ash under certain conditions


Minerals slowly work their way in to wood and fill the cells taking on the exact shape of the old cell



The resulting stone looks exactly like wood


The forces of erosion break down the petrified wood, leaving little "wood" chips littering the ground



Petrified wood is found on every continent except Antartica


The colors can vary widely due to various minerals in the soil



Petrified forests were live forests 65 million years ago


Nobody truly knows why some trees end up petrified, while others simply decompose