other names: Beryll
mineral class: Silicates and germanates
chemical formula: Be3al2(SiO3)6
Chemical elements: Beryllium, aluminum, silicon, oxygen
Similar minerals: see Beryll
colour: White blue
shine: Glass gloss
crystal structure: hexagonal
mass density: approx. 2.7
magnetism: not magnetic
Mohs hardness: 7 - 8
stroke color: White
transparency: Glass gloss
General information about aquamarine:
Of the aquamarine describes a mineral belonging to the Beryl family whose name means seawater and refers to its distinctive blue color. As one of the most famous and popular gemstones, aquamarine, like the emerald, belongs to the aluminum silicates. Aquamarine may appear both watery light blue and bright mid blue or greenish blue. Finest channels in the mineral, which may be filled with gases, liquids or mineral inclusions, often provide a delicate white pattern in the form of stripes. The mostly regular coloring of the mineral is due to the admixture of the trace element iron, which usually has a share of about two percent. Irregularities in the jewelry industry are corrected by heating the stone to four hundred degrees Celsius. Using this method, it is also possible to extract aquamarines from emeralds by converting the trivalent iron responsible for the green color into divalent. This reaction turns a green into a blue stone.
Like all beryls, the glassy, shiny and mostly transparent aquamarine forms prismatic crystals as well as aggregates of massive, columnar, radial or granular form. Aquamarines have a shell-like to brittle fracture, a perfect cleavage and a Mohs hardness of 8 maximum.
Occurrence and extraction:
Aquamarines are formed from magma rock and occur mainly in granite pegmatites, gneisses and hydrothermal rock veins. Often they are also found in granites as secondary parts. Socialization with other minerals such as topaz, quartz or feldspar is common.
The coveted stones are mined around the world, with the main deposits in Brazil, especially in the states of Minas Geras, Espirito Santo and Bahia. In Brazil in 1910 also the largest known aquamarine was found, which had a weight of 110 kilograms. Other economically significant sites are in Madagascar, Kenya, Nigeria, Malawi, Mozambique, Zambia, Pakistan, the United States and Russia, especially in the Urals and Siberia.
Use by humans:
As a gemstone, lucky charm and symbol of the young aquamarine has been highly sought after since antiquity. The ancient Romans and Greeks gave Aquamarine to the sailors to ensure a safe and, above all, economically successful journey. This tradition continued in the Middle Ages, when the aquamarine should serve as a lucky charm not only to the sailors, but also to the soldiers in the battle.
As a gem the aquamarine is still popular and can reach high prices depending on color intensity and size. Accordingly, there are also counterfeits on the market, which are made of colored glass, synthetic minerals or quartz. Particularly commendable are those stones that come from the Brazilian mine of Santa Maria de Itabira and therefore bear the name "Santa Maria".