Amorphous gems

Published December 28, 2017

Amorphous gems

Amorphous gems are those minerals or rocks that do not have a regular internal arrangement of atoms, characteristic of crystals. In the Greek language, amorphous means "formless", "not having a crystalline structure". Unlike crystals, amorphous substances do not solidify to form crystalline faces, and possess an isotropy of properties, that is, they do not exhibit differences in properties in different directions...

The caves

Published December 28, 2017

The caves

The caves are widespread on the earth. People have discovered only a small part of them, but very few have been studied so far. Caves arise mainly in "soluble" rocks: limestone, gypsum, anhydrite, mineral salts. Other rocks, for example granites, are incomparably more resistant to weathering and the destructive effect of underground groundwater. Therefore, in them caves practically do not arise...

Double refraction

Published December 28, 2017

Double refraction

Double refraction had its say in the famous dispute between Huygens and Newton about the nature of light: is it corpuscular or wave? In 1808, the Paris Academy of Sciences announced a competition for the best mathematical theory of birefringence of crystals. The competition won E. Malius (1775-1812), who discovered the polarization of light, as the solution to double refraction...

Electrical properties of minerals

Published December 28, 2017

Electrical properties of minerals

Electric properties of minerals have long been known to people. The ability of amber to electrify with friction is well described. Native metals, such as copper and silver, are excellent conductors of electricity. And such minerals as calcite or micas are no less excellent dielectrics. Suffice it to recall the marble shield-insulators...

Minerals

Published December 28, 2017

Minerals

It is not so easy to formulate the term "minerals". It can be said that minerals are substances of natural origin, which are chemical compounds or chemical elements. The term minera (lat.) means "a piece of ore", "ore". The concept of "mineral" does not have an unambiguous definition. The mineral is usually referred to as a natural chemical compound or chemical element formed as a result of various...

About mineralogy

Published December 28, 2017

About mineralogy

Mineralogy is the science of minerals. Minerals surrounded the person always and interest to them showed scientists in ancient times. An impulse to the birth and development of mineralogy during the first period was the discovery of natural crystals of quartz, pyrite, hematite, calcite, native copper. And already Aristotle (384-322 BC) and Theophrastus...

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