Minerals And Gems

Many of the minerals in the form of beautiful crystals, but the most popular of all are gems. Gemstones are often rough looking quite common. Only when cut and polished to achieve the brightness and brightness that makes them so valuable.

Precious stones were divided into classes historically precious and semiprecious stones. There are a number of semiprecious stones, many very nice, but diamonds, rubies, sapphires, emeralds and is described as "beautiful." (At one point, amethyst was also considered a precious jewel, but the large reserves are located in Brazil, reducing its value.)

Diamond carbon atoms, are naturally occurring substance found on Earth. Formed under extremely high pressure of hundreds of miles below the earth, can be found in very few places around the world. Graphite is also made of carbon atoms, but with a different arrangement, because diamond is the hardest mineral and graphite (used as a pencil) is one of the softest.

The jewels are made of a compound mineral called corundum, aluminum oxide. The red color is caused by traces of chromium. Corundum is also in many colors of sapphire, which are generally mixtures of traces of iron, titanium and chromium.

Emeralds are formed from a mineral called beryl whose chemical formula is a complex mixture of beryllium, aluminum, silicon and oxygen. Additional traces from chromium and vanadium. Various tracers can produce other colors, to form beryl semi-precious stones such as aquamarine.

Minerals and Gems are classified by their physical properties such as hardness, luster, color, density and magnetism. They are identified by how they are broken, or kind of mark or a line, they go when rubbed on a laboratory tool called the streak plate.