Click here for info about other gemstones

Click on the underlined links below, to see items for sale

Loose Stones - Rough & Slab - Spheres

Gold Rings - Gold Pendants - Gold Earrings - Gold Sets - Gold Bracelets
Silver Rings - Silver Pendants - Silver Earrings - Silver Sets - Silver Bracelets
Beads - Fashion Pins - Tie Tacks - Bola Ties


Arizona Petrified Wood

What is the Petrified Forest National Park?

Located in northeast Arizona, the Petrified
Forest National Park has some of the largest
logs of petrified wood in the greatest concen-
tration known to man. These trees, some of
which are over 200 ft tall and 10 feet wide,
possess world-renowned recognition for their
exquisite color and detail. The park was created
to preserve the remains of the ancient forests, the
currentnatural environment, and other resources
for public use and enjoyment. On the approximately
100,000 acres ofpark land, there are 5 forests you
can visit: the Jasper Forest, the Crystal Forest, the
Black Forest, the RainbowForest, and the Blue Mesa.
The petrified wood, coloredby a variety of minerals, is
found in the colored sand, silts and mud's that make up some of the badlands of the Painted Desert. The badlands, created from erosion, are colored from blue to red, and yellow to gray. But the trees are not all of the remains present, there's also some animal fossils and over 40 different ancient plant species. On top of that, there is a more recent history preserved there which includes the presence of Native American cultures.

How Does Wood Petrify?

Start with a semi tropical forest with a 200 foot canopy of conifers and tropical flora. Slow moving streams and swamps populated with fish, clams fallen logs and reptiles.

One of the most well-known fossils of the world, petrified wood is a fascinating example of mineral replacement. Petrified Wood is real wood that has turned into rock composed of
quartz crystals. The wood was covered with such agents as volcanic ash, volcanic mud flows, sediments in lakes and swamps or material washed in by violent floods.

Wood from primeval forests became buried by thick layers of sediments. This excluded
oxygen which prevented decay. A number of mineral substances (such as calcite, pyrite, marcasite) can cause petrifaction, but by far the most common is silica. Solutions of silica dissolved in ground water infiltrate the buried wood and through a complex chemical process are precipitated and left in the individual plant cells.

It is not wood that makes petrified wood colorful, but the chemistry of the petrifying groundwater. The silica can be agate, jasper, chalcedony or opal. The beautiful and varied colors of petrified wood are caused by the presence of other minerals that enter the wood in solution with the silica. Iron oxides stain the wood orange, rust, red or yellow. Manganese oxides produce blues, blacks or purple.

List of minerals and related color hues:
Copper - green/blue
Cobalt - green/blue
Chromium - green/blue
Manganese - pink
Carbon - black
Iron Oxides - red, brown, yellow
Manganese Oxides - black
Silica - white, Gary

Even though petrified wood is fragile, it is also harder than steel. Petrified wood is known for it's exquisite color and detail. Some pieces of petrified wood have retained the original cellular structure of the wood and the grain can easily be seen. Petrified wood can be found throughout the desert regions. It is easy to find and identify. It is used often in jewelry making and for other types of decorative artwork.

Petrifaction of the wood found in the Petrified Forest began during the Triassic Period around 180,000,000 years ago. Trapped in sediments that would eventual reach as much as 400 feet. The layer of sediments is known today as the Chinle Formation.

The petrified logs were buried in the sediment for millions of years, protected from the elements of decay. During this time the plain was covered by an ocean and another layer of sediment was deposited on top of the wood-rich Chinle Formation.

About 60 million years ago the ocean moved away and the erosion process began. More than 2600 feet of sediment have eroded to expose the top 100 feet of the Chinle Formation.

Petrified Wood is the official State Fossil of Arizona.

Click here to find locations for collecting precious and
semi-precious stones in Arizona? Look to BigArizona.com
for updates on some of Arizona's most popular sites and reports
on other sites that you may not have known existed.
http://www.bigarizona.com

Top