Aragonite
A variety of Aragonite Group
What is Aragonite?
Aragonite is widely and most popularly seen as the coating on pearls. It is also the main component of coral and stalagmites. It is remarkably brittle and comes in many different varieties, depending on the mineral in which it is found. It is truly a remarkable, morphing mineral!
Uses & Applications
Currently, there are no practical uses for aragonite. However, it is a constituent of limestone which is used in the production of cement and steel. Furthermore, one study has shown that aragonite may successfully remove pollutants such as zinc, cobalt, and lead from water.
Healing Properties
Aragonite is an energizing stone that is believed to improve self-confidence and promote self-discipline. It is an excellent stone for anyone learning patience and tolerance. Its positive energy stimulates motivation and puts a stop to procrastination. This not only allows the person to move forward in their life goals but also discourages feelings of anger and stress. Often used in meditation, its potent energies align and activate all of the chakras.
Optical Properties
- Refractive Index
- 1.525-1.686
- Birefringence
- 0.155
- Pleochroism
- Strong
- Optical Character
- Biaxial negative
Discover Values
Aragonite Market Value Calculator
Estimate the market value of Aragonite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.
Aragonite Localities Map
See where Aragonite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
Associated Chakras
Key Characteristics
Characteristics of Aragonite
Aragonite is thermodynamically unstable at standard temperature and pressure, and tends to alter to calcite on scales of 10 to 10 years. The mineral vaterite, also known as μ-CaCO3, is another phase of calcium carbonate that is metastable at ambient conditions typical of Earth's surface, and decomposes even more readily than aragonite.
Formation of Aragonite
The type location for aragonite is Molina de Aragón in the Province of Guadalajara in Castilla-La Mancha, Spain, for which it was named in 1797. Aragonite is found in this locality as cyclic twins inside gypsum and marls of the Keuper facies of Triassic. This type of aragonite deposit is very common in Spain, and there are also some in France and Morocco. An aragonite cave, the Ochtinská Aragonite Cave, is situated in Slovakia. In the US, aragonite in the form of stalactites and "cave flowers" (anthodite) is known from Carlsbad Caverns and other caves. Massive deposits of oolitic aragonite sand are found on the seabed in the Bahamas. Aragonite is the high pressure polymorph of calcium carbonate. As such, it occurs in high pressure metamorphic rocks such as those formed at subduction zones. Aragonite forms naturally in almost all mollusk shells, and as the calcareous endoskeleton of warm- and cold-water corals (Scleractinia). Several serpulids have aragonitic tubes. Because the mineral deposition in mollusk shells is strongly biologically controlled, some crystal forms are distinctively different from those of inorganic aragonite. In some mollusks, the entire shell is aragonite; in others, aragonite forms only discrete parts of a bimineralic shell (aragonite plus calcite). The nacreous layer of the aragonite fossil shells of some extinct ammonites forms an iridescent material called ammolite. Aragonite also forms in the ocean and in caves as inorganic precipitates called marine cements and speleothems, respectively. Aragonite is not uncommon in serpentinites where high Mg in pore solutions apparently inhibits calcite growth and promotes aragonite precipitation. Aragonite is metastable at the low pressures near the Earth's surface and is thus commonly replaced by calcite in fossils. Aragonite older than the Carboniferous is essentially unknown. It can also be synthesized by adding a calcium chloride solution to a sodium carbonate solution at temperatures above 60 °C (140 °F) or in water-ethanol mixtures at ambient temperatures.
Quick Facts
Physical Properties
- Color
- Colorless, white, grey, blue, green, red or violet
- Hardness (Mohs)
- 3.5 - 4
- Density
- 2.944 g/cm³
- Streak
- Colorless, white
- Luster
- Vitreous, Resinous
- Crystal System
- Orthorhombic
Chemical Properties
- Chemical Formula
- CaCO3
- Elements
- C, Ca, O
Also Known As
Identify Aragonite Instantly
- Snap a photo, get instant results
- 6,700+ rocks, minerals & crystals
- Discover collecting spots near you
