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Latest Calcite Stories

Ancient Climate Change Evidence From Fossilized Plankton
2013-10-26 05:41:11

redOrbit Staff & Wire Reports - Your Universe Online Climate change dating as far back as hundreds of million years ago was recorded in the shells of ancient oceanic plankton, according to new research published in the journal Earth and Planetary Sciences Letters. Typically, scientists analyze polar ice in search of information about the planet’s temperature and atmosphere, but the oldest Antarctic ice core records only date back to approximately 800,000 years ago. In the new...

2012-04-03 08:40:22

Corals may be better placed to cope with the gradual acidification of the world´s oceans than previously thought — giving rise to hopes that coral reefs might escape climatic devastation. In new research published in the journal Nature Climate Change, an international scientific team has identified a powerful internal mechanism that could enable some corals and their symbiotic algae to counter the adverse impact of a more acidic ocean. As humans release ever-larger amounts of...

Structure Of Tough Sea Urchin Spines May Inspire Engineers
2012-02-16 14:10:27

A team of German scientists recently decoded the molecular structure of the unusually sturdy spines of sea urchins, a discovery that they believe could eventually prove useful in helping engineers construct stronger, more stable buildings. Biologists have long known that the spines of the globular little marine animals are made of the compound calcium carbonate, a chemical commonly found in the shells of various invertebrates, not to mention egg shells, calcium supplements and the antacids...

2011-05-10 16:02:52

The acidification of the world's oceans could have major consequences for the marine environment. New research shows that coccoliths, which are an important part of the marine environment, dissolve when seawater acidifies. Associate Professor Tue Hassenkam and colleagues at the Nano-Science Center, University of Copenhagen, are the first to have measured how individual coccoliths react to water with different degrees of acidity. Coccoliths are very small shells of calcium carbonate that...

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2011-02-23 10:56:19

An international research team, with Spanish participation, has discovered a new species of mollusk, Polyconites hadriani, in various parts of the Iberian Peninsula. The researchers say this species, which is the oldest in its genus, adapted to the acidification of the oceans that took place while it was in existence. This process could now determine the evolution of modern marine systems. The new species Polyconites hadriani, which was discovered in 2007, has been crowned the oldest in the...

4f1dd5ddbc07f25308a3e381b4642a4f
2011-02-02 06:00:00

Researchers in Britain and Denmark have unveiled an "Ëœinvisibility cloak' that uses a common crystalline material known as calcite, which works by sending its two "polarizations" of light in different directions. Cloaking involves guiding light waves in such a way that waves from a hidden object do not reach the eye.  By using calcite, the researchers created an "Ëœinvisibility cloak' that hid a small (inch-size), three-dimensional object.  However, the size of...

2010-11-18 09:15:00

The ability to tell the difference between crystals that formed naturally and those formed by human activity can be important to archaeologists in the field. This can be a crucial bit of information in determining the ancient activities that took place at a site, yet archaeologists often wait for months for the results of laboratory tests. Now, however, an international team of physicists, archaeologists and materials scientists has developed a process that can tell in a matter of minutes the...

6b604c1311781263aa087c385655aae7
2010-07-15 06:35:00

Which came first: the chicken or the egg? It is an age old question that has spurred on many a debate, but now a group of scientists might actually be close to having an answer. Using cutting-edge technology, researchers from the Universities of Sheffield and Warwick in England believe that they have discovered the answer by studying eggshells. Scientists had long theorized that a chicken protein known as ovocledidin-17 (OC-17) played a crucial role in the formation of an egg's shell, but...

2010-03-08 12:47:48

Scientists have made synthetic "Ëœsea shells' from a mixture of chalk and polystyrene cups "“ and produced a tough new material that could make our homes and offices more durable. A team of materials scientists and chemists have taken inspiration from sea shells found on the beach to create a composite material from dissimilar "Ëœingredients'. Their technique could be used to make ceramics with high resistance to cracking "“ which could in turn be used in...

2ccbd123c4f0f4fb3d24c63eaf2a6d8d1
2009-05-27 08:32:14

Overfishing and disease have decimated shellfish populations in many of the world's temperate estuarine and coastal ecosystems. Smithsonian scientists, led by Whitman Miller, ecologist at the Smithsonian Environmental Research Center in Edgewater, Md., have discovered another serious threat to these valuable filter feeders"”rising levels of atmospheric carbon dioxide that contribute to the acidification of open ocean, coastal and estuarine waters. Their findings are being published in...


Latest Calcite Reference Libraries

28_3f12abda63415a07ee5b6c5d30ef8239
2005-05-26 12:17:18

Aragonite is a polymorph of the mineral calcite, both having the chemical composition CaCO3. Its structure differs from calcite and leads to a different crystal shape, an orthorhombic system with acicular crystals. By repeated twinning pseudo-hexagonal forms result. It may be columnar or fibrous, occasionally in branching stalactitic forms called flos-ferri (flowers of iron) from their association with the ores at the Carthinian iron mines. The type location for aragonite is Molina de...

28_9c404ab9a4754b403781670c9e631915
2005-05-26 11:59:32

he mineral calcite is a calcium carbonate corresponding to the formula CaCO3 and is one of the most widely distributed minerals on the Earth's surface. It is a common constituent of sedimentary rocks, limestone in particular. It is also the primary mineral in metamorphic marble. It also occurs as a vein mineral in deposits from hot springs, and also occurs in caverns as stalactites and stalagmites. Calcite is often the primary constituent of the shells of marine organisms (e.g. plankton,...

28_af149e6f4821ab4ec3c213f12d27e305
2005-05-26 09:38:30

Limestone is a sedimentary rock composed of the mineral calcite (calcium carbonate). The primary source of this calcite is usually marine organisms. These organisms secrete shells that settle out of the water column and are deposited on ocean floors as pelagic ooze (see lysocline for information on calcite dissolution). Secondary calcite may also be deposited by supersaturated meteoric waters (groundwater that precipitates the material in caves). This produces speleothems such as stalagmites...

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Word of the Day
lunula
  • A small crescent-shaped structure or marking, especially the white area at the base of a fingernail that resembles a half-moon.
This word is a diminutive of the Latin 'luna,' moon.
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