Can granite be radioactively dated?
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For something to be dated using a radioactive technique, it has to include radioactive materials. Granite is radioactive (see attached), but its level of radioactivity is usually quite low (no more than any other natural material). This makes dating granite a bit challenging, but it can be done (see example in 2nd reference). Granite usually contains a little U-238 which does decay, and this can be used to date granite. It also contains some Rb-87 which decays into Sr-87, and the Rb-Sr dating techniques can be used to date granite.
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The currently accepted estimate is 4.5 to 4.6 billion years old.  Radiometric dating of Earth rocks can't get us there because the surface of the Earth has undergone so much upheaval.\n \nInstead, moon rocks and meteorites are used to estimate the age of the Earth, because it appears that all of the solar system formed at about the same time.\n\nCarbon dating is of no use here; it only works for organic material and it can't date back further than 50,000 years or so. Long-lived radioactive elements such as uranium are used instead.
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No. It will make a very poor fireplace liner. You should use a firebrick if possible.  These are made specifically for fireplaces and kilns and can be laid with a fire clay in the joints, or none at all. \n\nThe problem with using granite is that it will spall from the heat and eventually may disintegrate. Granite is composed of grains of quartz, feldspar, mica and sometimes hornblende and other minerals. Each of these has a slightly different reaction to the heat, and the expansion and cooling from a fireplace will eventually cause your granite to fall apart. \n\nThat said, if you don't mind replacing the liner once in while I am sure you could do it. I'm sure that a century ago when firebrick where hard to obtain that many people used whatever rock was available. The only precaution I would take is being sure the rock is dry before you build a fire, or you may have small explosions and cracking from the moisture. \n\nI've built a few fireplaces with my dad.
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Which isotope?\n\nThorium-232 has a half-life of 14 billion (14x109) years, and decays by alpha emission, with accompanying gamma radiation. Thorium-232 is the top of a long decay series that contains key radionuclides such as radium-228, its direct decay product, and radon-220. \n\nTwo other isotopes of thorium, which can be significant in the environment, are thorium-230 and thorium-228. Both belong to other decay series. They also decay by alpha emission, with accompanying gamma radiation, and have half-lives of 75,400 years and 1.9 years, respectively
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http://www.acstones.com/gemofmonth/2001/gemofmonth.8.01.html
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No. Radiocarbon dating relys on Carbon 14 which has a half-life of 5730±40 years. Most answers for carbon dating give a range of 100-200 years over when a sample might be from.\n\nIn addition to the half-life, you also need to know something about where the carbon in the sample came from, because different sources have different starting amounts of C14. \n\nThis means that carbon dating something modern would tell you it was made in the last 100 years. You could probably get a better estimate of the age, just by looking at it.
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Carbon-14 dating is reliable for dating objects up to about 60,000 years old, the half-life of the isotope (5730 years) does not allow for accurate dating on objects much older than that.  Also, it is difficult to accurately date recent objects, as changing levels of carbon due to use of fossil fuels and nuclear explosions have changed the equilibrium of C-14 with its atmospheric production rate.  \n\nAlso, experiments have failed to show that half-lives of isotopes have changed as time has passed, therefore we can consider half-lives to be stable.  \n\nIn summary, we can consider radiocarbon dating accurate, as long as we are not considering objects older than about 60,000 years, (other radiometric dating methods are used for older objects) or recent objects.  People who claim that scientists misdate dinosaur bones as weeks old are misleading, as dinosaur bones are dated with uranium and rubidium, rather than C-14 (since they are millions of years old).  \n\nHope this is helpful.
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Carbon-14 is only reliable for dating objects up to about 60,000 years old.  The website below explains the equation in detail if your interested.
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Radioactive dating is dating using the decay of naturally occuring biologically acive materials. The most common is carbon. Carbon 14 is created at a more or less constant rate in the environment and then decays, so is found at a fixed proportion in relation to carbon 12. This is the proportion found in living organisms. When they die, they take up no more carbon, so the carbon 14 decay causes the ratio to change in a way that can be used for dating..\n\nNo. The moon has moved 90 degrees in relation to the earth and so is now in quadrature with the sun.\n\nThe solar cycle is the cyclical variation in sun spots on the surface of the sun. Sunspots are caused by loops of magentic flux. Their reduction is caused by shedding entagled loops of field.\n\nComets tails point away from the sun because of the solar wind. Far from the sun comets have no tails.\n\nThe corona is hot but thin. So light from it is swamped by light from the rest of the sun usually. In an eclipse the moon blocks light from the rest of the sun.
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The latest studies place the oldest rock formation in the canyon at 1.84 billion years old.  Note that you have to be somewhat careful when discussing the age of the rocks at the bottom of the Grand Canyon as the dates have become more refined with improved dating techniques while books and literature often quote older, outdated numbers that have since been revised.\n\nOne of the most recent published studies about the age of rocks in the Grand Canyon's inner gorge is that by geologist K. E. Karlstrom and others.  They identify the Elves Chasm pluton (a granite intrusion in the western end of the canyon) as the oldest rock formation in the canyon (and in the southwest US for that matter) at a date of 1.84 Ga (1.84 billion years old).  They also date most of the other rocks of the inner gorge (a variety of schists, gneisses and other granite plutons) over a range of 1.65 to 1.75 Ga (1.65 - 1.75 billion years old).\n\nThese dates place the oldest rocks of the inner gorge near the end of the geologic time frame known as the Paleoproterozic Era (which is the period from 1.6 to 2.5 billion years ago) when the North American continent was still forming and life was limited mostly to simple algaes.  \n\nNote that for many years, the inner gorge rocks were believed to be somewhat older (2 billion years or more) and were once even assigned to the earlier Archean period.  These somewhat older dates and classifications are still sometimes given in books, web pages, etc.\n\nLastly... I have the seen the Vishnu Schist complex that makes up much of the inner gorge added to the phrase mentioned above as 'Know The Canyon History, See Rocks Made By Time, Very Slowly' (Very Slowly = Vishnu Schist).
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http://www.pubs.asce.org/WWWdisplay.cgi?9605225\nSaprolite is a rare find in our area.  We've found it in a few parking lots, and we can buy it from only a few dealers.\n\nSaprolite is also called "rotten granite" -- it really is granite that's been partially changed by thousands or millions of years of weathering. \n\nhttp://saltthesandbox.org/rocks/saprolite.htm\n\nProperties\n1.Saprolite forms when granite and other igneous and \nmetamorphic rocks are exposed to humid climates for \nthousands or millions of years. \n2.Saprolite is mostly reddish in color.\n3.Its crystals are usually pea-sized or smaller\n4.it started out as granite\n5.Is made mostly of the minerals feldspar and quartz, and may also contain small crystals of mica or darker minerals.
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ok. i am giving u links which will help u find the right information fast and efficiently. since you have to write in ur words, its better that u deduce the answers urself. it should be quite simple and it will help you.\n\nbasically granite is an igneous rock which is formed due to the cooling down and crystallization of molten magma. here are the links which will help u. there is a file included which is quite informative.\n\nMost of the sites have overlapping information, so use the info u need. Have fun and do cite the links as the sources
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Yes.\n\nOrthoclase feldspar is an example.  At high temperatures, Fe will fit into the orthoclase lattice.  As temperature drops, the lattice shrinks so that Fe no longer fits.  Fe diffuses out of the latice and accumulates along the planes between orthoclase crystal twins.  Along the way, it grabs O to produce Fe2O3.  If you look closely at pink granite, usually you will see that the pink grains are actually white and red striped.  Those grains are orthoclase crystals with exsolved hematite along twin planes.\n\nExsolution and diffusion of Fe from orthoclase can only occur at high temperature.  If the orthoclase cools too quickly for the Fe to diffuse out, it will remain in the orthoclase lattice, which will be distorted to accomodate the larger (larger than K) Fe ion.\n\nMaterial science is not boring.
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I'll tell you and won't kill you.\n\nBut don't even think of trying this at home.\n\nThe ore (found in rocks, mines, mountains) contains a couple types (isotopes) of uranium, mainly  U-235 (the one for nuclear fuel) and U-238 (depleted uranium, for armor piercing rounds).\n\nThese have different weights, so you can use a centrifuge (same as the spinner that seperates blood cells from plasma based on weight) to seperate the lighter atoms of U-235 from the heavier U-238. Thus all the fuss about who may or may not be buying aluminum tubes in the middle east to make centrifuges.
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Granite and Marble are use to make Tombstones.
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The age of a fossil may be specified in both relative terms (how old it is in relation to other fossils or rock units) and in absolute terms (approximately how many years old it is). One principle of relative dating is called superposition, which holds that in any one place, the lower rock layers (and fossils in them) are older than higher ones, unless there is evidence that the layers have been overturned. This is logical, since the lower sediments would have been deposited first. A related concept is correlation, whereby rock layers (strata) are compared with others in another location on the basis of their mineral composition, fossil content, and other features. When a rock unit or series closely matches those of another area, they are said to be correlated and considered to be of similar age. Correlations are especially reliable when they include index fossils, which are fossils with a limited age range. Good index fossils are easily recognized and widely distributed around the world, so that they aid both local and international correlations.\n\nAbsolute dating complements relative dating by providing a specific (not necessarily precise) chronological age for a given specimen, such as "50 million years before present." In recent years reliable forms of absolute dating became available through the development of radiometric dating methods. These methods are based on the known, regular decay of certain radioactive elements (isotopes) into other isotopes or "daughter products." By measuring the amount of "parent" and "daughter" products in a rock sample, its approximate age may be calculated.\n\nMany people have heard of the Carbon 14 method and assume that fossils are dated by it. Actually, in most cases the C-14 method is useful only on organic material less than about 50,000 years old, which includes many human remains and artifacts, but excludes most fossils. Absolute dating of fossils requires other dating methods such as the potassium-argon or rubidium-strontium methods, which involve isotopes with slower decay rates (longer "half-lives"). Such isotopes are rare in fossils themselves, but may occur in surrounding or adjoining rock layers, yielding an approximate age for the fossil-bearing unit. Using the principles discussed above, scientists also can deduce the approximate age of other layers correlated with the same formation, as well as an approximate age for layers above and below the formation (which would be somewhat younger and older respectively).\n\nThe terms "above" and "below" in this context are used in a relative or stratigraphic sense; that is, they are based on the positions of the units relative to each other (or correlated units), rather than their height above sea level. The branch of geology that deals with the correlation of rock layers is known as stratigraphy (or biostratigraphy when focusing on the fossils within the layers), and is an important tool of paleontologists.
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OK, first geography is NOT geology *sigh*\n\nLook up carbon dating; you can either tell by the degradation of carbon or by basic layering (what's on the bottom is older than what's on the top).