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Quartz
Quartz is one of the most common minerals in the Earth's continental crust. It belongs to the hexagonal crystal system, and is made up of silica (SiO2) tetrahedra. Quartz has a hardness of 7 on the Mohs scale. Density is 2.65 g/cm³. The typical shape is a six-sided prism that ends in six-sided pyramids, although these are often twinned, distorted, or so massive that only part of the shape is apparent from a mined specimen. Additionally a bed is a common form, particularly for varieties such as amethyst, where the crystals grow up from a matrix and thus only one termination pyramid is present. A quartz geode consists of a hollow rock (usually with an approximately spherical shape) with a core lined with a bed of crystals.
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Earth & Climate News
October 29, 2026
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Oct. 26, 2026 Arctic winter sea ice could disappear much faster than scientists previously expected, according to new research using climate clues from 6,000 years ago. By comparing ancient ocean sediments with modern climate models, researchers found that future ...
Oct. 23, 2026 Switzerland’s glaciers are disappearing at an alarming rate, losing more than 5% of their ice volume in 2026 alone. Some of the country’s most famous glaciers experienced their worst melting on record, while several smaller glaciers vanished ...
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Oct. 21, 2026 Scientists have cracked a 178-year-old mystery surrounding a train delayed by a solar storm, revealing that the famous incident happened in 1848 rather than 1841. The discovery rewrites the early history of space weather and highlights a threat that ...
Oct. 20, 2026 A new study reveals that improved hurricane forecast graphics may help people identify threatened areas without making them more likely to recognize the danger or take protective action. Researchers also found that a widespread misunderstanding of ...
Oct. 19, 2026 A massive landslide in Alaska triggered the second-highest tsunami ever recorded, sending water and debris 1,580 feet up a mountainside just hours after tourists visited the area. Scientists discovered that the disaster was preceded by several ...
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Latest Headlines
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Oct. 28, 2026 Scientists have discovered that magma deep inside Earth can store surprising amounts of extra oxygen, potentially revealing a hidden contributor to our planet's oxygen-rich atmosphere. The findings ...
Oct. 28, 2026 Scientists have uncovered a long-lost volcanic system in Iran that dates back roughly 100 million years, revealing a hidden chapter in Earth's tectonic history. The discovery sheds new light on the ...
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Oct. 21, 2026 Scientists discovered a rock in Papua New Guinea that plunged more than 90 kilometers beneath Earth's surface, revealing a bizarre temperature pattern that challenges established theories of Earth's ...
Oct. 21, 2026 A decades-long mystery beneath the North Sea has finally been solved. Scientists have confirmed that the Silverpit Crater, buried 700 meters below ...
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