Physical and Chemical
Colour: from light to dark rose. It varies according to its
chemical composition. When the percentage of elements that substitute
manganese is high, rhodochrosite´s colour is lighter.
Brightness: from vitreous to nacreous
Fracture: irregular - translucent - semihard
Specific Gravity: from 3.3 to 3.7
Hardness: from 3.5 to 4 (this is the reason why it acquires a good
A dark patina appears on its cover when it is exposed to the air due to the manganese
oxidation. It becomes darker gradually if it is heated up. It is insoluble in cold
hydrochloric acid (which makes it different from Rose Calcite), but it is soluble in hot
hydrochloric acid (which makes it different from Rhodonite).
Appearance and Presentation
It is one of the most attractive stones because of its structure and its
unique colour. It was called the "National Argentinean Stone" and it is used as
a semiprecious stone.
Its striped structure has strata or crusts. Rose bands of different tonalities are
superposed. This tonalities go from the light to the dark ones. The rose bands have a
fibrous structure and they are separated by a white or grey material (a mixture of
carbonates: Calcium, Magnesium, Iron, and a low concentration of Manganese Carbonate).
The rose bands are straight or wavy and they sometimes have a mammillary form.
The rhombohedric, flat and perfect crystals with a lenght of 3 to 5 mm are highly valued.
These crystals are rose to light rose coloured and usually form druses.
It can be found in the form of stalactites which, when sliced into circles, show
concentric bands. A stalactite can be formed by several straight or curved growing centres
which can reach a length of 30 cm and a diameter of 2 to 8 cm or more.
It can be found along with copper, silver and lead sulphides, as well as with
manganese minerals, in metalliferous hydrothermal lodes of medium temperature. It is
commonly found as a sedimentary mineral.
Origin and Deposit Location
It has a volcanic origin and it is located in a volcanic shaft formed by Riolite,
Tufa and Breccia. It is located in the Capillitas Sierras in the
"Nevado of Aconquija", in the province of Catamarca, Argentina. It is
at 3,200 metres above sea level.
The iron industry uses the manganese that the mineral contains. The polished
stone is often used to make ornamental objects. Once carved it can be used as a
semiprecious stone. At present, scientists and collectors are interested in this
It is a soft stone and it acquires an incredible shine when polished. It can be used
in ornamentation, decorative objects and jewelry.
First quality polished
Slidef of estalactites
Carved pieces for