Rhodochrosite
- Rhodochrosite
- Inca Rose
- Rosenspat
- Himbeerspat
Rhodochrosite, also outdated as rhodochrosite, Inca Rose, Rosenspat or Himbeerspat known, is a common mineral from the mineral class " carbonates and nitrates " (formerly known as carbonates, nitrates and borates ). It crystallizes in the trigonal crystal system with the composition Mn [ CO3 ], and is therefore chemically seen a manganese carbonate.
Rhodochrosite usually develops rhombohedral or scalenohedral crystals, but also globular or grape-like and granular to massive aggregates of pink to red or brown, rarely white in color with white stroke color. Often Rhodochrosite occurs concentrically banded and with black, crusty coatings or in the form of contact twins. In addition, it forms various pseudomorphs among other things for shells.
With a Mohs hardness of 3.5 to 4.5 is Rhodochrosite between the soft and medium hard minerals joins, which can easily be scratched with a knife. Yet he is popular due to its mostly vigorous rose red to raspberry- red color and its lively gloss or glass due to its eye-catching banding as a gemstone.
Special Features
Rhodochrosite is readily soluble in hot acids and decomposes ( dissociated ) at about 650 ° C.
Rarely, there are also Rhodochrosite that fluoresce under ultraviolet light pink - purple.
Etymology and history
Abraham Gottlob Werner (1749-1817) named the mineral due to its chemical composition and its good cleavage initially as rhodochrosite.
By Friedrich Hausmann (1782-1859), it received 1813 final name of " Rhodochrosite ".
This is derived from the ancient Greek language, the first part of the word - " Rhododendron " - there in the Attic dialect as ῥόδον [r ʰ Odon ] or the aiolischen dialect βρόδον [br ʰ Odon ] " Rose ( nduft ) " occurs and already in Mycenaean Greek
as
Later on August Breithaupt (1791-1873) suggested alternatively currently the names Rosenspat and Himbeerspat because he kept the name Rhodochrosite for evil sounding and difficult to pronounce.
As a type locality for rhodochrosite is considered the " Cavnic Mine" in Romania.
Classification
In the now outdated but still in use 8th edition of the mineral classification by Strunz the Rhodochrosite " water outdoors carbonates without foreign anions " belonged to the common mineral class of " carbonates, nitrates and borates " and then to the Department of where he together with calcite, Gaspéit, magnesite, Otavit, siderite, smithsonite, and vaterite Sphärocobaltit the " Calcitgruppe " with the system no. V/B.02 formed.
The 9th edition used since 2001 and valid by the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Rhodochrosite in the class of " carbonates and nitrates " ( here, the borates form a separate class) and then in the Department of " carbonates without further anions, without H2O ". This division, however, is further subdivided according to the nature of the cations involved, so that the mineral is found according to its composition in the subsection " alkaline-earth (and other M2 ) carbonates ", where it together with calcite, Gaspéit, magnesite, Otavit, siderite, Smithsonite and Sphärocobaltit the " Calcitgruppe " with the system no. 5.AB.05 forms.
The classification of minerals according to Dana assigns the rhodochrosite as the outdated 8th edition of the Strunz'schen systematics in the common class of " carbonates, nitrates and borates " and there in the department of " water clear carbonates ". Here he is with calcite, magnesite, siderite, Sphärocobaltit, Smithsonite, Otavit and Gaspéit in the " Calcitgruppe ( trigonal R - 3c)" with the system no. 14:01:01 within the sub-division of " water clear carbonates CO3 with a simple formula A " to find.
Education and Locations
Rhodochrosite forms as a primary mineral in medium-to low-grade hydrothermal veins, where it is usually found in paragenesis with barite, calcite, dolomite, fluorite, Hübnerit, pyrite, quartz, siderite, sphalerite and tetrahedrite; or in some metamorphic rocks of sedimentary origin usually together with Alabandin, garnet, rhodonite and hausmannite.
The classical banding occurs, similar to a lime stalactite, formed by the influence of water and the associated layer-wise deposition of dissolved minerals in the water flow. The fluctuating mineral concentration of the water is different deposition layers and thus the characteristic pattern.
Worldwide, Rhodochrosite so far (as of 2011) are detected at about 1,400 localities. Apart from its type locality " Cavnic Mine", which is also known for its pink- colored, globular, nierigen aggregates, the mineral in Romania still found in some other places in Maramureş County and in Baia de Aries and Roşia Montană in Alba County and Suceava in the same circle.
Noteworthy due to their significant Rhodochrositfunde is among other things the " Sweet Home Mine" at Alma (Colorado), in which up to 15 cm wide, rhombohedral crystals were revealed. Up to 10 cm wide, scalenohedral and strong dark red crystals mines 1 and 2 were found in Kuruman in South African N'Chwaning and about 8 cm Rhodochrositrhomben found in Silverton (Colorado). Locality beautiful crystals of the mineral was also the pit wolf in the winner country as well as smaller mines in the Rheingau ( Geisenheim ) and near Bingen ( Waldalgesheim ) in Germany.
Important deposits of the mineral are located in Butte, Montana, where the mineral is mined as manganese ore, in Colorado, another state in the U.S., next in Mexico, Argentina, Brazil, African countries Gabon and South Africa, Romania, Russia and Japan.
More Locations are Afghanistan, Armenia, Australia, Belgium, Bolivia, Bosnia and Herzegovina, Brazil, Bulgaria, Chile, China, Ecuador, Finland, France, Gabon, Georgia, Ghana, Greece, Greenland, Honduras, India, Indonesia, Ireland, Isle of Man, Italy, Japan, Kazakhstan, Kyrgyzstan, Kosovo, Macedonia, Mexico, Mongolia, Namibia, New Caledonia, New Zealand, Norway, Austria, Papua New Guinea, Peru, Philippines, Poland, Portugal, Russia, Saudi Arabia, Slovakia, Sweden, Switzerland, Spain, South Korea, Taiwan, Turkey, Ukraine, the United Kingdom ( UK) and the United States of America.
Even in rock samples of the Baltic Sea near Gotland Rhodochrosite is found.
Crystal structure
Rhodochrosite crystallizes isotypic with calcite trigonal space group R3c ( Raumgruppen-Nr. 167) with the lattice parameters a = 4.77 Å and c = 15.63 Å and 6 formula units per unit cell.
Use
As a raw material
Rhodochrosite is used due to its high manganese content of up to 47.8 % as an important manganese ore.
As a gemstone
Rhodochrosite is also used as a gemstone since about the 1950s. Clear Rhodochrositkristalle gem quality are rarely found. Since the pink white banded aggregates, however, are drawn similarly striking how different agates and Rhodonite, the processed into jewelry or arts and crafts objects Rhodochrosite increasingly popular. Especially popular are gems of raspberry- red color.
To make the harness and drawing of the stone come into play better, for one of the cabochon cut and on the other the use of larger pieces is preferred.
Depending on which color to accept the clear or banded varieties of Rhodochrosits, they can be confused with various other minerals, so among other things with the fire opal, rhodonite, rose quartz, tourmaline and Tugtupite