Sample 7 Colors: white veins, grey, light and dark brown. Predominant minerals: silicon, iron oxide and carbon, typical of Madagascar. Sample 8 Colors: white veins, grey, black, light and dark brown. Predominant minerals: silicon, calcium and carbon, typical of Madagascar.
Sample 9 Colors: white veins, red and light brown. Predominant minerals: silicon, iron oxide and magnesium, typical of Madagascar. Sample 10 Colors: white, red orange and dark brown veins. Predominant minerals: silicon, iron oxide and magnesium, typical of Arizona and Madagascar. Sample 11 Colors: white veins, red orange and light brown. Sample 12 Colors: black, grey, light brown and red veins.
Nowadays, a good-looking slab of petrified wood can sell for hundreds or even thousands of dollars. This is to say nothing of the wood's scientific value — which is considerable. When we look at petrified wood, we're looking at a long-dead tree that was turned to stone and yet still retained its basic structure. How is such a transformation possible?
Well, it can only take place under the right set of circumstances. When an organism dies, it usually decomposes. Such is the circle of life. The process that most people call " rotting " is a type of decay which sets in as microorganisms break down organic matter. Usually, a dead, fallen tree will be subjected to this process.
Once in a while, though, a newly-deceased tree or some other kind of woody plant gets rapidly buried by mud, silt or volcanic ash. This blanketing material then shields the dead tree from oxygen. Because oxygen is the main driving force behind the decaying process, the smothered plant will begin to decompose far more slowly than it normally would.
Meanwhile, mineral-laden water or mud seeps into the dead tree's pores and other openings. As our plant's internal structure gradually breaks down, its organic material wood fibers gets replaced by silica and other minerals. Over a period of a few million years, those minerals will crystalize. The end result is a rock that appropriates the shape and structure of our original tree. The level of detail we find in some specimens is downright astonishing.
A completely charcoal black petrified wood piece is rare and it requires a true connoisseur's eyes to appreciate the textural markings in the subtle variations of charcoal black.
The white color is petrified wood is due to the presence of Silicon Dioxide, commonly known as free Silica, occuring in the form of quartz. Blue and purple hues in petrified wood are created by the presence of manganese dioxide. This tan color in petrified wood is the most common color of petrified wood.
In this case, the structure of the wood is preserved better and produces an appearance or actual wood. This is due to the presence of silica dioxide. The land we see today is an arid desert scattered with wood that has since turned to stone. Petrified wood is real wood that has turned into rock composed of quartz crystals. One of the greatest concentrations of petrified wood in the world is found in the Petrified Forest National Park in northeast Arizona. Logs as long as feet long and 10 feet in diameter have been found in the park.
What turned the wood to stone? Petrified wood has been preserved for millions of years by the process of petrification. This process turns the wood into quartz crystal which is very brittle and shatters. Even though petrified wood is fragile, it is also harder than steel. Petrified wood is known for its 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.
0コメント