![]() ![]() The Eh-pH diagrams tailored to each combination of minerals with organic matter allow to estimate the original conditions of mineralization and give the indications for the potential biomimetic synthesis. Lignin is most often met among the remains of the primary organic matter and is clearly observed in all kinds of wood, except the apatite-calcite one. The analysis of preserved cells permineralized with two minerals allows tracing both the structure of cell walls and the remains of ancient organic matter. The application of synchrotron radiation for X-ray microdiffraction analysis of petrified wood is presented and compared to elemental (electron microprobe) and molecular (micro Raman) analyses with the use of table-top instruments. The samples cover nearly the whole time of tree existence on the Earth. Several kinds of petrified wood with different combinations of minerals have been studied: apatite – calcite calcite – pyrite hematite – gypsum wood quartz - goethite goethite – calcite woods, from different countries and estimated as old in the time range of 1.8–306 MA. The first flowering plants (as we know them today) expanded to world wide dominance during the Cretaceous Period which began 1,350 million years ago.Fossilized wood belongs to the most exciting, however, rarely studied objects in nature. As each original tree and minerals infusion are entirely unique, each piece of petrified wood is completely one of a kind - if you purchase a piece of petrified wood it will not be the same as any other. Cycads and conifers were dominant during the Jurassic Period starting about 180 million years ago. Petrified wood is an extraordinary gift from nature, a relic that has been present on earth for millions of years. During the Triassic Period (225 to 190 million years ago) conifers such as the Araucaria of the Arizona Petrified Forest increased. 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. White wood also may be the result of weathering - color having been bleached out. ![]() 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. (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. This kind of fossils is very interesting as one can. 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 a remnant material from distant epochs that was fossilized in a mineralized form. Petrified Woodstone will strengthen your devotion to the person you love and provide you with the endurance to survive the storms. It will envelop you in a gentle and caring embrace, making you feel safe and comfortable. ![]() 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. Petrified Wood is a protective stone in general. 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. The process of petrification of wood is still not well understood by scientists. ![]()
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