|Petrified Wood is actually wood that has been turned into stone by a Geologic process called petrification (or
petrifaction). It may be beautifully colored by chemical impurities such as iron and copper. Petrification takes place
through a combination of two similar processes called permineralization and replacement. Minerals either fill all of
the pores and cavities of the organic matter (permineralization), or mineral bearing water dissolves the original
organic material and replaces it with mineral matter (replacement). The minerals form a perfect copy of the original
substance, including cell structure and fibers. The replacement mineral is usually a variety of quartz, chalcedony,
opal, calcite, or carnotite. These processes can replicate the original specimen down to the microscopic level.
There are two common types of permineralization, they are silicification and pyritization.
Silicification is the process in which organic matter becomes saturated with silica. Silicification generally occurs in
two environments. The specimen may have been buried in sediments of deltas and flood plains, or the specimen
may have been buried in volcanic ash. The process begins when a specimen is saturated with a silica bearing
water. The cell walls of the specimen are eventually dissolved and silica is deposited into the empty spaces. This is
the process that makes Petrified Wood. The cellulose and lignin (two components of wood) are degraded and
replaced with silica. The specimen is then transformed to stone in a process called lithification (a process whereby
freshly deposited loose grains of sediment are converted into rock) as water is lost.
Pyritization is a process similar to silicification, but instead of silica, this process involves the deposits of iron and
sulfur in the pores and cavities of an organism. This process is what forms Pyritized Ammonites
Replacement is the second process involved in petrification. Replacement occurs when mineral bearing water
dissolves the original solid material of an organism and replaces them with minerals. This process is extremely
slow, but results in the replication of the microscopic structure of the organism. The slower this process is, the better
defined the microscopic structure will be. The minerals commonly involved in replacement are calcite, silica, pyrite,
and hematite. It is rare to find organisms preserved by replacement alone, but these specimens can be extremely
detailed. Most petrification occurs with replacement in combination with permineralization.
The rate at which petrifaction occurs is not exactly known. Most petrified wood was formed long ago. Stone logs in
Petrified Forest National Park, Arizona, are of the Triassic Period and more than 160,000,000 years old.
Petrified forests were formed in different geologic periods. The trees in each one represent the species that grew
during the period of its formation. The oldest Petrified Forest in the United States that we know of is the Devonian
trees near Gilboa, New York. There are amazing areas of petrified wood in Yellowstone National Park, including a
few very rare upright fossilized tree trunks. Gingko Petrified Forest is a state park in Washington. Deposits of
petrified wood have also been found in California, New Mexico, and Utah. Our favorite to visit is still the Petrified
Forest National Park, Arizona! Here is a link to their website...
Here are some youtube Links we think you might find interesting to watch!
Petrified Forest National Park, Arizona
Video 1409 of a reality travel show with your host David Rush. Go to www.davidrush.net
Petrified Wood - 15 million-year-old Petrified Tree
Geologist describes process that turned 15 million-year-old logs to stone near Vantage, Washington.
http://hugefloods.com/ presents "2 Minute Geology" episode that tells the story of logs protected from lava by lake
water. Today the beautiful petrified logs are on display at Ginkgo Petrified Forest State Park
|Photos of petrified wood logs at Petrified Forest National Park
(photos courtesy of pdphoto.org)
|Peanut Wood is a “Petrified Wood” but it is not a land based Petrified Wood like
you might find in Arizona. This petrification process started when wood was
swept into the ocean. The ocean washed and eroded the wood making it into
something like driftwood that you might find on a beach today. While floating in
the ocean, this driftwood was invaded by a breed of mollusks named Teredo
(commonly called “Shipworms”). They are notorious for boring into and often
destroying wood that is immersed in sea water. Structures like wooden piers,
docks and wood hull ships are often destroyed by these “termites of the sea” that
tunnel with a pair of very small shells they have at one end. This tunneling is often
described as “rasping their way through the wood”. The wood gets heavier as it
gets waterlogged and is filled with these shipworms and eventually settles to the
bottom of the ocean where the bore holes become filled with layers of whitish-tan
colored mud and sediment and quartz petrification occurs. It is believed that these
stones are around 120 million years old. The name Peanut Wood was given to
the petrified wood because the lightly colored boreholes resemble peanuts in a
coffee or toffee brown quartz petrification. This petrified wood is often referred to
as a gemstone because the solid quartz petrification lends itself to making
excellent cabochons. It is found along the edges of the Kennedy Ranges about
100 miles inland from the coastal town of Carnarvon, Western Australia.
1.23 lb Polished Face Thick
Peanut Wood DisplaySlab
|This exceptional and extra large specimen of Peanut Wood from Australia has been in our personal collection since around 1995.
It was procured from a mineral dealer in Deming New Mexico. It is a nice slab just shy if 1 inch thick. It can be kept as a display
slab or cut into more slabs or cabochon stock. This piece has natural faults typical of this material. Takes an excellent polish.
This slab weighs 19.8 oz or 1.23 lb (561 grams) and measures approximately 3.1 x 3.2 x 0.96" (15.7 x 8.3 x 2.44 cm)
|Whitish background is natural...it was frosty outside today!