Related topics: quantum computing · carbon

New species of mastodon discovered in California

A team of researchers affiliated with several institutions in the U.S. has discovered a new species of mastodon. In their paper uploaded to the peer-reviewed journal PeerJ, the group describes discovering the new species ...

A tip for future nanoscale sensing

Commercially-available diamond tips used in atomic force microscopy (AFM) could help make quantum nanoscale sensing cost-effective and practical, A*STAR researchers have found.

Spare 10 minutes to make science leap forward

Today sees the launch of an innovative Citizen Science Project by Diamond Light Source, the UK's national synchrotron science facility.The project uses a crowdsourcing model to call on people of all ages around the world ...

Nano-sized diamond will improve materials for maritime transport

An experiment on the introduction of nanoscale diamond into an aluminum melt using ultrasonic treatment at the Brunel University (London, United Kingdom) has been completed. The result will be used to create new materials, ...

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Diamond

In mineralogy, diamond (from the ancient Greek αδάμας – adámas "unbreakable") is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions. Diamond is renowned as a material with superlative physical qualities, most of which originate from the strong covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material. Those properties determine the major industrial application of diamond in cutting and polishing tools.

Diamond has remarkable optical characteristics. Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron and nitrogen. Combined with wide transparency, this results in the clear, colorless appearance of most natural diamonds. Small amounts of defects or impurities (about one per million of lattice atoms) color diamond blue (boron), yellow (nitrogen), brown (lattice defects), green (radiation exposure), purple, pink, orange or red. Diamond also has relatively high optical dispersion (ability to disperse light of different colors), which results in its characteristic luster. Excellent optical and mechanical properties, combined with efficient marketing, make diamond the most popular gemstone.

Most natural diamonds are formed at high-pressure high-temperature conditions existing at depths of 140 to 190 kilometers (87 to 120 mi) in the Earth mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years (25% to 75% of the age of the Earth). Diamonds are brought close to the Earth surface through deep volcanic eruptions by a magma, which cools into igneous rocks known as kimberlites and lamproites. Diamonds can also be produced synthetically in a high-pressure high-temperature process which approximately simulates the conditions in the Earth mantle. An alternative, and completely different growth technique is chemical vapor deposition (CVD). Several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have been developed to distinguish natural and synthetic diamonds and diamond simulants.

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