Aragonite is named after the province of Aragon in Spain, where the mineral was found for the first time.
Its Composition is Ca [CO3], containing Sr, Ba, Pb, Mg, Fe, Zn, etc.
Aragonite and calcite have the same chemical composition but different crystal structures. The crystals of Aragonite may be plate, needle or prismatic, and the two ends are like pyramids.
Aragonite precipitates in warm seawater and becomes calcite over the years. In addition, Aragonite will be formed in metamorphic rocks that have experienced high pressure.
Basic properties of Aragonite
[Form] It belongs to orthorhombic system. It is in tabular, tapered, columnar, and thatched shapes. Pseudohexagonal columnar triplets and contact twins are common. The aggregates are often in rod, radial, stalactite, bean, Burman, fiber, shell, and crystal family shapes.
[Optical property] Glass luster, shell-like fracture, grease luster, transparent to translucent. Cleavage parallelism is incomplete.
The streak is white, and the Mohs hardness is 3.5~4.0. The density is 2.9~3.0 g/cm. When it interacts with cold dilute hydrochloric acid bubbles violently.
Refractive index N=1.5961, Nm=1.6174, N=1.6218. Aragonite is similar to calcite, but Aragonite has no rhombohedral cleavage, and its density is slightly higher than calcite.
[Hardness] 3.5-4
[Cleavage] good Cleavage in a direction; Incomplete Cleavage in the other two directions
[Stripes]white
[Gloss] Glass luster, turpentine luster
[Color] White, gray, light yellow, light red to black, etc. When Ca is replaced by Sr and Cu, light blue, blue-green and purple red will appear.
[Chemical Composition]
The chemical composition is CaCO3, Ca is often replaced by Sr, Pb, and Zn elements. Known varieties include Aragonite, lead aragonite, zinc aragonite, and rare earth aragonite. In addition, sometimes, it contains Mg, Fe, Cu, etc.
[Origin] In nature, Aragonite is much less than calcite. Aragonite is mainly formed in low-temperature hydrothermal and exogenic conditions.
Aragonite formed by endogenesis is the product of the last stage of hydrothermal process, which is commonly found in the pores and fractures of hot spring sediments and volcanic rocks.
Aragonite can also be formed by biochemical action, which is the main mineral component of shells and pearls.
Aragonite also occurs in the surface oxidation zone of metal deposits. Major producing areas in the world: China, Argentina, Australia, Belgium, Bolivia, Canada, Spain, etc.
China’s main producing areas are Wenshan and Lanping in Yunnan and Qinglong in Guizhou.
[Others] Transparent to translucent; Fluorescent
Key Points for Aragonite identification
Aragonite is a kind of low-temperature mineral. Because single crystal is rare, Aragonite often appears as aggregate. It is distinguished from calcite and dolomite by its biaxial and incomplete Cleavage.
If the Aragonite with good quality, after polishing and processing, presents beautiful colors and concentric circles, which can be made into ornaments, printing materials, etc.
In addition, it can be used as specimen and ornamental stone in terms of color, shape, artistic conception, etc.
Light blue-green and blue Aragonite are rare and precious in the world. They are a wonder among mineral ornamental stones and are loved by collectors of rare stones.
Characteristics of Aragonite in Yunnan
Yunnan aragonite is famous in China. Its main producing areas are Wenshan, Lanping, Zhenkang, Gejiu, Zhaotong, Dongchuan and other places.
The Fusi aragonite found in the surface oxidation zone of the Yanzidong deposit in Baiqiuping silver polymetallic mining area, Lanping County, is light blue or light blue-green, glassy, shell-like, kidney like or fibrous aggregates and has a dense structure.
In the limestone and basalt fissures in Gejiu, Jianshui and Zhaotong areas, stalactite, shell-like and grape-like Aragonite are produced. Generally, 1~15cm thick, light blue, and some stripes can be dark blue, which may be related to the rock containing Sr (limestone) and Cu (basalt).
In the Wenshan area (Yangpi Village, Tieze, Laohuilong and other places in Dehou, Wenshan County), there are crystal family, stalactite and bean-shaped aragonites in the karst landform, which are generally white, gray white, translucent, some like flowers, some like goblets, with various shapes and very beautiful.
Light blue and light yellow aragonites are also produced in Luziyuan, Dakuangshan and the riverside areas of Zhenkang County.
Aragonite, calcite and dolomite Comparision
Aragonite has less mineral reserves than calcite. It is mainly formed in metamorphic rocks and sedimentary rocks, and also exists in shells or bones of some animals.
It also occurs in seawater and sediments around hot springs. The crystal of Aragonite is columnar, usually double crystal.
If the double crystal is staggered, it is hexagonal, generally in the form of columnar, stalactite and fibrous aggregates;
The colors are white, colorless, gray, green, blue, etc.; The streak is white, transparent to translucent, with glass or grease luster. The major source of Aragonite in the world is California in the United States.
Calcite is a widely distributed mineral, which is an essential component of limestone and marble.
It is mainly formed in limestone. Calcium bicarbonate dissolved in solution can also precipitate into calcite under appropriate conditions.
The crystal shapes of calcite are various, usually rhombohedral or triangular, bicrystal, mainly in granular, massive, stalactitic, fibrous and crystal group aggregates;
The color ranges from colorless to white, red, green, black, etc., among which colorless and transparent crystals are called Iceland stones; Transparent to translucent, with glass luster or pearl luster.
Calcite can be made into solvent in metallurgical industry and cement and lime in construction industry.
Iceland spar is a high-grade material for making polarizing prisms, and calcite has a wide range of practicability.
Dolomite is an essential mineral component of dolomite and dolomitic limestone.
It is mainly formed in hot veins or magnesium-richmagnesium-rich metamorphic rocks and occurs in the pores of crystalline limestone and carbonate rocks.
Sometimes, as the cement of various sedimentary rocks, it is the most common rock-forming mineral in carbonate rocks.
The crystal structure of dolomite is similar to that of calcite, which is usually rhombohedron, with curved crystal surface in horseshoe shape, mainly in massive and granular aggregates.
The color of pure dolomite is white, and it will be gray, pink or brown when containing other impurities; The streak is white, from transparent to translucent, with glass luster or pearl luster.
Dolomite has strong practicability and is widely used in various fields such as architecture, chemical industry, agriculture, environmental protection, energy conservation, etc. It is mainly used to make fluxes and alkaline and refractory materials for blast furnace ironmaking.
In addition, it can also be used to produce calcium magnesium phosphate fertilizer and magnesium sulfate.
Aragonite Healing Property
In crystal therapy, you can make friends with hurt feelings, walk on the ground, place aragonite at the heart chakra, and with deep and long breathing, visualize Aragonite’s white light entering the body, helping to relieve emotional distress.
A friend who is too sentimental and easy to be emotional can form a chest pendant of Aragonite and hang it in the heart chakra solar nerve, which will help people to be freer, more open and happier.
For overly rational people, they often test family and friendship. Please always gaze at the beautiful Aragonite and gently touch the position of the third eye, which will help to bring human feelings, be more considerate of others, and have a sense of humor.
For some Excessive shrewd businessmen, they always get max costs, benefits, etc. It May cause others to be unhappy. It is necessary to wear Aragonite to make them win the respect of others.
Conclusion:
Aragonite is a mineral composed of calcium carbonate and calcite with the same chemical composition. Aragonite is unstable in nature and often turns into calcite, so the output of Aragonite is not as good as calcite.
The Aragonite is produced in high-pressure metamorphic rocks, sedimentary rocks, hot spring sediments, etc.
The crystals are mainly columnar, and there are also three columnar crystals forming hexagonal columnar twin crystals.
In addition, there are also small granular crystals like dew, coral-like aggregates called “mountain corals,” and various crystal aggregation forms such as fibrous.
We can distinguish Aragonite and calcite according to Cleavage, occurrence state, crystal shape, etc.