Rhodochrosite from Sweet Home Mine, Alma, Colorado, USA

Pink is the most common color of Rhodochrosite. Specimen mined near Silverton, Colorado

Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO₃. In its (rare) pure form, it is typically a rose-red color, but impure specimens can be shades of pink to pale brown. The streak is white. Its Mohs hardness varies between 3.5 and 4. Its specific gravity is 3.5 to 3.7. It crystallizes in the trigonal system. The cleavage is typical rhombohedral carbonate cleavage in three directions. Crystal twinning often is present. It is transparent to translucent with refractive indices of nω=1.814 - 1.816 nε=1.596 - 1.598. It is often confused with the manganese silicate, rhodonite, but is distinctly softer. Image File history File linksMetadata Size of this preview: 800 × 532 pixelsFull resolution (3008 × 2000 pixel, file size: 4. ... Image File history File linksMetadata Size of this preview: 800 × 532 pixelsFull resolution (3008 × 2000 pixel, file size: 4. ... Rhodochrosite from Sweet Home Mine, Alma, Colorado, USA Pink is the most common color of Rhodochrosite. ... Alma is a town located in Park County, Colorado. ... Image File history File linksMetadata Size of this preview: 800 × 532 pixelsFull resolution (3008 × 2000 pixel, file size: 3. ... Image File history File linksMetadata Size of this preview: 800 × 532 pixelsFull resolution (3008 × 2000 pixel, file size: 3. ... Official language(s) English Capital Denver Largest city Denver Area  Ranked 8th  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ... General Name, Symbol, Number manganese, Mn, 25 Chemical series transition metals Group, Period, Block 7, 4, d Appearance silvery metallic Standard atomic weight 54. ... In organic chemistry, a carbonate is a salt of carbonic acid. ... A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. ... Two pounds of Manganese Carbonate powder and a seventeen pound house cat. ... Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer. ... Relative density (also known as specific gravity) is a measure of the density of a material. ... Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite planes, creating smooth surfaces, of which there are several named types: Basal cleavage: cleavage parallel to the base of a crystal, or to the plane of the lateral axes. ... It has been suggested that twin boundary be merged into this article or section. ... The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ... A piece of rhodonite Rhodonite is a member of the pyroxene group of minerals, consisting of manganese inosilicate, (Mn,Fe,Mg,Ca)SiO3, and crystallizing in the triclinic system. ...

Rhodochrosite forms a complete solid solution series with iron carbonate (siderite). Calcium, (as well as magnesium and zinc, to a limited extent) frequently substitutes for manganese in the structure, leading to lighter shades of red and pink, depending on the degree of substitution. It is for this reason that the most common color encountered is pink. Fig. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... Siderite is also the name of a type of iron meteorite. ... General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Standard atomic weight 40. ... General Name, Symbol, Number magnesium, Mg, 12 Chemical series alkaline earth metals Group, Period, Block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Appearance bluish pale gray Standard atomic weight 65. ...

Rhodochrosite occurs as a hydrothermal vein mineral along with other manganese minerals in low temperature ore deposits as in the silver mines of Romania where it was first found. Banded rhodochrosite is mined in Capillitas, Argentina. Catamarca, Argentina has an old inca silver mine that has produced fine stalatitic examples of rhodochrosite that are unique and very attractive. Cut cross-sections reveal concentric bands of light and dark rose colored layers. These specimens are carved and used for many ornamental purposes.[1]

Its main use is as an ore of manganese which is a key component of low-cost stainless steel formulations and certain alluminium alloys. Quality banded specimens are often used for decorative stones and jewelry. Due to its being relatively soft, and having perfect cleaveage, it is very difficult to cut, and therefore rarely found faceted in jewelry. General Name, Symbol, Number manganese, Mn, 25 Chemical series transition metals Group, Period, Block 7, 4, d Appearance silvery metallic Standard atomic weight 54. ... Jewelry (the American spelling; spelled jewellery in Commonwealth English) consists of ornamental devices worn by persons, typically made with gems and precious metals. ...

It was first described in 1813 in reference to a sample from Cavnic, Maramureş, present-day Romania. The name is derived from the Greek word for rose-colored.

Colorado officially named Rhodochrosite as its state mineral in 2002 based on a proposal by a local high school (Platte Canyon High School in Bailey,Colorado). The reason for this lies in the fact that while the mineral is found worldwide, large red crystals are found only in a few places on earth, and some of the best specimens have been found in the Sweet Home Mine near Alma, Colorado. Official language(s) English Capital Denver Largest city Denver Area  Ranked 8th  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ... Alma is a town located in Park County, Colorado. ...

The Alma King is the largest known rhodochrosite crystal; it was found in the Sweet Home Mine near Alma, Colorado. It is on display in the Denver Museum of Nature and Science.

Image File history File linksMetadata Size of this preview: 533 × 599 pixelsFull resolution (2052 × 2307 pixel, file size: 1. ... Image File history File linksMetadata Size of this preview: 533 × 599 pixelsFull resolution (2052 × 2307 pixel, file size: 1. ... Rhodochrosite from Sweet Home Mine, Alma, Colorado, USA Pink is the most common color of Rhodochrosite. ... Alma is a town located in Park County, Colorado. ... Denver Museum of Nature and Science The Denver Museum Of Nature and Science (DMNS) is the main natural history museum in Denver, Colorado. ...

Rhodochrosite and Silver Mining

Manganese carbonate is extremely destructive to the amalgamation process used in the concentration of silver ores, and so until quality mineral specimens became highly sought after by collectors, they were often discarded on the mine dump.

References

• Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., ISBN 0-471-80580-7
• Mindat
• Webmineral data
• Mineral galleries