History of Onyx

According to legend this gem would have been created when Cupid cut the nails of the sleeping Venus and scattered them on the ground. The Romans went to use the name Onyx only for black and dark brown chalcedony. Like the Agate, the Onyx is also a gem with stripes.

Onyx is a stratified variety of chalcedony, like agate. They are differentiated by the shape of the bands, since those of the onyx are parallel and those of the agate are curved. Its chemical nomenclature is SiO2 (silicon dioxide). Some varieties are considered “semi-precious stones”. The most striking are those with bands of contrasting colors. Those presented in black and white, for example, are widely used in cameos (relief obtained in precious stone). And in ancient times the Romans used them to decorate different objects of ornament.

Black onyx is said to promote vigor, strength and perseverance, help to learn the lessons by imparting self-confidence and helping you to be in harmony with your surroundings, it is a protection stone, due to the way it repels and deflects negative energy.

Minerology: It has a volcanic origin, originated by the accumulation of volcanic      gases, they are varieties of chalcedony, colored bands create brown, white or black marks on the stone, they have a fine grain texture. Chalcedony is a form of quartz, making onyx stones look and feel crystalline. it is black due to iron and manganese deposits.

Etymology: It comes from the Greek “onux”, which means nail.

 Mineral class: Oxides, group of quart

 Chemical formula: SiO2

 Hardness : 7 on the Mohs scale.

 Field: Italy, Mexico, Brazil, Russia, South Africa, Pakistan.

History of Marble

This stone began to be worked in the 6th century in Ancient Greece, where the image of the marble worker also appeared, which means, the person who works it. The result of the crystallization of the limestone became a fundamental element for the construction and sculpture of the Greeks.

From the point of view of the arts, the concept of marble is established according to its appearance, limestone being susceptible to a fine polish, achieved thanks to the compactness of the formation of its agglomerated materials. The concept of marble is even accepted and extended to rocks that have a finish appearance similar in appearance to marble, despite the fact that in its composition, the presence of calcium carbonate is scarce or null.

Marble was highly valued in ancient times and became the favorite material of Greek and Roman sculptors and architects, becoming a symbol of power. It is also a cultural symbol of tradition and refined taste.

In geology, marble is a compact metamorphic rock formed from limestone rocks that, subjected to high temperatures and pressures, reach a high degree of crystallization. The basic component of marble is calcium carbonate, whose content exceeds 90%; the other components are those that give a great variety of colors to the marbles and define their physical characteristics. After an abrasion polishing process, the marble reaches a high level of natural shine, that is, without waxes or chemical components. Marble is mainly used in construction, decoration and sculpture. Sometimes it is translucent, of different colors, such as white, chestnut, red, green, black, gray, yellow, blue, and can appear uniformly colored, marbled (with speckles), veined (hatched lines) and various configurations or mixtures between them.

Properties

• Marble composition: 90% crystallized CaCO3 calcium carbonate. The remaining ten percent can be in different compositions:
• Hardness: 3 to 4 on the Mohs scale
• Hardness 3: can be scratched with a copper coin
• Hardness 4: can be scratched with a steel knife
• Marble is translucent, it allows light to pass easily.
• Density: A liter of marble weighs between 2.6 and 2.8 kilos.

Interesting Marble Facts

Marble has been used to make statues and provide flooring since ancient times. Plaster fresco has been used as a marble replacement when marble is too expensive to use. Marble is a type of metamorphic rock.

Marble is mainly white, but it can also come in other colors.

In ancient times, you could easily see where a piece of marble came from by looking at its color.

Marble has been used to make statues and provide floors since ancient times.

Plaster fresco has been used as a replacement for marble when marble is too expensive to use.

Marble generally originates as limestone or dolomite.

Calcite, dolomite crystals, and aragonite are the key components of marble.

Impurities are what give marble its color.

Marble is typically found among other metamorphic rocks such as gneiss and mica shale.

Marble is generally found among the oldest part of the earth’s crust.