Petrify wood11/2/2022 Cycads and conifers were dominant during the Jurassic Period starting about 180 million years ago. This kind of fossils is very interesting as one can. During the Triassic Period (225 to 190 million years ago) conifers such as the Araucaria of the Arizona Petrified Forest increased. Petrified wood is a remnant material from distant epochs that was fossilized in a mineralized form. Throughout the world, petrified wood may occur in rocks of all ages since the Upper Silurian Period (440 to 410 million years ago) when the first land plants evolved. In time, the insides of wood are not wood anymore. Water from the river or a lake delivers minerals to the wood. Petrification happens when trees, plants, and remains of animals are naturally buried by ash, soil, and silt. White wood also may be the result of weathering - color having been bleached out. Petrified wood is the result of years and years of natural preservation of wood. Petrified woods of pure silica are white, tan, or gray. Cinnabar produces a true rose or baby pink, and chlorite, a deep green. Chromium in wood gives a lovely soft green. Some of the most brilliant oranges and bright yellows result from the presence of carnotite - a compound of uranium. Petrified Wood is a sedimentary rock composed of mostly silicate minerals like quartz along with calcite, opal, and pyrite on occasion. (Dendritic forms of manganese produce black picture patterns). Manganese oxide produces blues, blacks, or purple. Iron oxide stains the wood orange, rust, red, or yellow. 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. Assemblages of such named woods from the same collecting area can enable us to recreate pictures of the ancient forests of the past. Petrified wood is often presented in classrooms as an example of great age - for it obviously takes a long, long time to petrify wood, right But knowledgeable. The finest anatomical details of cell structure (as in living wood) may be preserved positive identification as to species is then possible with the use of high - powered magnification. So accurate is the preservation in many woods that the worm holes with castings, borer holes with insect eggs, fungus-rot, dry rot, and growth abnormalities of all kinds are faithfully reproduced. During petrification the wood is often so well preserved that it's appearance remains almost unchanged only it's weight, when lifted, tells that it has turned to stone. Even precious opal may occur as it does at Virgin Valley, Nevada. Here the silica may take a variety of forms it may be agate, jasper, chalcedony, or opal. Solutions of silica dissolved in ground water infiltrate the buried wood and by some complex chemical process are precipitated and left in the individual plant cells. A number of mineral substances (such as calcite, pyrite, and marcasite) can cause petrification, but by far the most common is silica. Wood (or other plant parts) must first be covered with such agents as ash from erupting volcanos, by volcanic mud flows, sediments in lakes and swamps or material washed in by violent floods - by any means, which would exclude oxygen and thus prevent decay. In spite of many attempts, man has not been able to duplicate this process in the laboratory. Stools and coffee tables are the standout uses of petrified wood in furniture, but it is becoming more common to see slabs of it used as decorative features in homewares.The process of petrification of wood is still not well understood by scientists. Petrified wood has similar qualities to stone and it can be polished to create durable and stunning pieces of furniture.Īside from having durable qualities it also looks extremely interesting, and El'ise's coffee tables are a perfect example of how a simple piece can add big impact to a room. (Nine) Why is petrified wood used to make furniture? The unique fossils are used to make furniture. It can take thousands of years for the organic remains of the piece of wood to be replaced by minerals and turned into stone. How long does it take for a piece of wood to petrify? For example copper gives a green or blue colour, while iron gives a red, brown and yellow colour to the wood - but most pieces of petrified wood look and feel like a smooth tree stump. If there are elements like iron and copper in the mud or water during the petrification process it can change the colour of the wood.
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