Can you help make this a better article? What good localities have we missed? Can you supply pictures of better specimens than those we show here? Can you give us more and better information about the specimens from these localities? Can you supply better geological or historical information on these localities?
Rhodochrosite
Mn2+CO3 trigonal
Rhodochrosite has been around as a mineral since the late 1700s when it was recognized as being a mineral with manganese and oxygen and as a manganese carbonate since the 1800s. The name rhodochrosite dates from the early 1800s. The Germans called it rosenspath.
1 Early texts like Dana 6th say that distinct crystals are not common which seems to be at odds with the plentiful images of beautiful rhodochrosite crystals that seem to be everywhere when you go looking for pictures of rhodochrosite. Rhodochrosite is not always red, but quite often pink and even brown and in colors aproaching white. It is one of the rhombohedral carbonates but not all rhodochrosite is pure end member manganese carbonate. There is a complete series where Mn
2+Fe
2+, Ca and probably Mg can substitute for each other in various degrees.
2,
3 Those rhodochrosites that contain mostly manganese in their structure, especially the nice red, fairly transparent ones are amazing impervious to reacting with concentrated hydrochloric acid. To see any reaction at all with even concentrated hydrochloric acid, you must grind it to a very fine powder, and even then it reacts slowly. When I last checked, Mindat has something over 1100 images of rhodochrosite from a little more than forty localitys that produce respectable specimens. It is found in hydrothermal veins that were formed in low to moderate-temperature ranges, metamorphic deposits and is common in carbonatites, authigenic and secondary sediments, but uncommon in granite pegmatites.
3 Fine red crystals of rhodochrosite are highly sought after by collectors and individual specimens from the Sweet Home Mine in Colorado have sold for more than a million dollars and fine miniature size specimens for many tens of thousands.
1. A System of Mineralogy, Dana, 6th edition1892, p.279. 2. Dana's System of Mineralogy, Palache, Berman & Frondell, Vol 2. p.171. 3. Handbook of Mineralogy, Anthony, Bideaux, Blada & Nichols, Vol. V, p.590. 3. 1. Mineralogical Record, Sweet Home Mine Issue, July-August, 1998, Vol. 29 No. 4. p.123-127.
[Rock Currier, 2 January 2009]
Rhodochrosite
Argentina
Catamarca, Andalgalá, Capillitas Mine
This mine has been producing mostly cutting grade rhodochrosite for more than 50 years. When I was in Argentina I investigated the possibility of buying some rhodochrosite and was directed to a government agency and was told I would have to deal with them. The mine was aparently owned by the gevernment and was considered part of their strategic copper reserve, though I never saw a copper mineral from the mine. Over on the western side of the Andes Mountains in Chile, the place is lousy with copper mines, but they don't have many in Argentina. Much of the rhodochrosite from the mine is a nice rose pink in color and frequently banded. Collectors cherish the stalactites of rhodochrosite from the mine which are up to about two feet tall and perhaps as much as eight inches in diameter. It they can't get a good one of those, they will even sit still for putting a cut and polished stalactite section in their collections. The stalactites are never cheap, because they can be cut up into many stalactite sections and a ready market is available for them. The best grade of rhodochrosite from the mine is called Ortiz quality, apparently named after the vein in the mine that produced it. It is a much darker pink, almost red color and is highly sought after by lapidaries for cutting into beads, cabochons and other small objects. Not much is available and it has been years since I saw any quantity of it.
[Rock Currier, 2 January 2009]
Rhodochrosite
Australia
New South Wales, Yancowinna Co., Broken Hill
The mines at Broken hill are not particularly known for their rhodochrosite specimens, but they have produced some nice specimens, though most if not all are a light pink color and not very red. But good ones are still cherished by collectors. We need someone to tell us more about them and which kinds came from which mines.
[Rock Currier, 2 January 2009]
Rhodochrosite
Australia
Tasmania, Rosebery district, Williamsford, Mt. Read, Hercules Mine.
There is a local argument that many of these specimens came from the nearby Rosebery mine, where collecting was rewarded with instant dismissal, but the mineral occurs in both mines. A good number of specimens came on the market in the 1970's, and were usually in crusts of rhombohedral crystals to 10mm or so, with a pale pink colour. It is probably calcian, as at Broken Hill, and is typically associated with crystals of quartz and fibrous boulangerite. Kutnahorite also occurs at Rosebery, and is similar in appearance, but paler.
[Ralph Bottrill]
Rhodochrosite
Brazil
Southeast Region, Minas Gerais, Conselheiro Lafaiete (old Queluz de Minas)
We need someone to tell us about the rhodochrosites from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Bulgaria
Plovdiv Oblast, Rhodope Mts. Madan
We need someone to tell us about the rhodochrosites from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Canada
British Colombia, Slocan Minind Division, Riondel, Blue Bell Mine.
We need someone to tell us about the rhodochrosite specimens from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Canada
Quebec, Rouville Co. Mont Saint Hilaire, Poudrette quarry.
 |
| © Russell G. Rizzo |
St. Hilaire is not particularly known for its rhodochrosite specimens, but I think it produced a greater variety of interesting rhodochrosite specimens than any other locality in the world. We need a St. Hilaire specialist to help us out on this article.
[Rock Currier, 2 January 2009]
Rhodochrosite
China
Zhuang Autonomous Region, Guanxi
With the recent flood of fine minerals from China we should not be surprised that some good rhodochrosite specimens have been found as well. We need someone to tell us about rhodochrosites from Zuang.
[Rock Currier, 2 January 2009]
Rhodochrosite
Gabon
Haut-Ogooué, Moanda, Moanda Mine.
Moanda is a shallow open cast mine that for the most part produces very uninteresting manganese ore. But every once in a while they find very pretty specimens of rhodochrosite though the crystals are never very large. All the ones I have seen have been little pointy ones. Sometimes they encounter specimens with tiny shiny black manganite crystals that will never pose a threat to their giant cousins from Germany.
[Rock Currier, 2 January 2009]
Rhodochrosite
Germany
Hesse, Limburg, Staffel, Heinricherz Mine
We need someone to tell us about the Rhodochrosite from this locality
Rhodochrosite
Germany
Rhineland-Palatinate, Taunus Mts, Niederneisen, Oberneisen, Rothenberg Mine (Seitersfeld)
The two specimens pictures on the left are amongst the very best that the locality has produced. For those wishing to find out more about the Rhodochrosites from the Rhineland-Palatinate the following book contains a selection of spectacular photographs of rarities from the collections at Mainz, focussing on minerals from Rhineland-Palatinate (incl. western Siegerland, Bad Ems, the mercury deposit near Obermoschel and other mining districts) and neighbouring areas: Poser, C., and Lutz, H. (2004): Mineralien aus Rheinland-Pfalz. Landessammlung für Naturkunde (Mainz), 80 pp. (in German)
[Peter Haas 2009
We need someone to tell us about the rhodochrosite specimens from this locality.
Rhodochrosite
Germany
Reinland-Palatinate, Hunsrück Mts., Waldalgesheim, Dr. Geier Mine (Dr. Geir Manganese Mine, Dr. Geir Dolomite Mine) Elisenhöhe Mine)
For what follows we must thank Roger Lang, obviously a charter member of the legendary "Red-Green Mafia" of Germany, who among other things points out the obvious, namely that good Rhodochrosites from German localities are highly prised and rarely on the market.
Specimens
The Dr. Geier mine has been well known for very nice rhodochrosite specimens ranging in colour from intense raspberry pink to brown. The rhodochrosite mostly forms botryoidal aggregates and reniform masses on iron/manganese oxides or ferriferous limestone/dolostone. The most sought after specimens were translucent pink single "balls" or crystal aggregates on lustrous pyrolusite/manganite providing a beautiful contrast. The "balls" mostly have a diameter of a few mm, the largest ones reached about cm size. Rhodochrosites from Waldalgesheim belong to the best of the species found in Germany. They are mentioned in the same breath as the specimens from Wolf mine, Herdorf and Oberneisen. Most of the rhodochrosite specimens from Dr. Geier mine have been recovered in the Elisenhöhe part of the mine at the so called yellow and green levels. They are comparable to the rhodochrosites from Rothenberg mine, Oberneisen, Heinricherz Mine, Staffel, and Schloßberg Mine, Geisenheim.
Other minerals worth mentioning from the Dr. Geier mine include pyrolusite and manganite crystals up to a few mm lenght as well as brownish pinkish to ivory whitish dolomite crystals up to 1.5 cm. Aragonite crystals as whitish acicular sprays reach 3 cm. Remarkeable is epsomite as up to 10 cm long acicular crystals and aggregates. Epsomite also occurs as crusts, fibrous masses and sometimes ramshorn like formations. The other minerals listed from here are only of local interest. Besides the minerals mentioned above the following species are known: calcite, chalcopyrite, copper, gypsum, "limonite", malachite, pyrite, quartz and romanèchite.
Geology
The iron and manganese ores of the Dr. Geier mine are hosted by Middle Devonian dolostones within an isoclinal through at the southern border of the variscan Rheinisches Schiefergebirge. Genetically they are related to the paleo-karst of the carbonate rocks overlain by marine sands of Oligocene age. Their formation is bound to cavities, caverns, sinkholes and dolines which formed within massive dolomite zones and zones with strong tectonic impact like fractures, joint-sets and bedding planes of the through structure during an uplift-period in the Eocene and the Lower Oligocene.
Up to 50 % of the doline fillings are Tertiary sands and clays. The ores are of mixed iron-manganese type with a Fe: Mn ratio of approx. 2:1. They contain variable amounts of muscovite (10–50%), goethite (30–50%), amorphous Mn oxides (20–30%) and manganite and pyrolusite ("Hartmanganerz", 0–22%). Their formation can be explained by a mixture of descendant colloidal solutions of Fe and Mn hydroxides under oxidizing conditions of the karst hydrography. The Mn and Fe can be deducted from weathered neighboring devonian shales of the Schiefergebirge and the dolomites. The ore grades were 12 – 20 wt.% Mn and averaging 29 wt.% Fe.
History
History
The oldest reports on manganese mining in the area date from the 17th century. At least since 1808 the Concordia mine near Seibersbach - a few km west of Waldalgesheim - was in operation. In 1832 the Sahler brothers were granted a concession to mine, followed by the Elisenhöhe claim in 1839 and the Waldalgesheim claim in 1840. Contineous mining began in 1880 by the Wandesleben brothers in open cuts. From 1885 Dr. Heinrich Claudius Geier of Mainz started extensive exploration works and sank the first shaft. These activities led to 12 concessions (mining claims) on manganese and iron. In 1904 the Gewerkschaft Braunsteinwerke Dr. Geier was founded and in 1911 all mines and concessions of the Gebr. Wandesleben GmbH (Concordia and Elisenhöhe mines, Waldalgesheim claim) were incorporated. A 7.5 km cableway to the river Rhine was built in 1912 to facilitate the ore transport to the shipping station. 1917 marks the year of the highest Mn ore production (240,853 t). At the same time the construction of the new main shaft was started (Straubenschacht). The ore was used for ironworks and partly as a pigment ore for ceramics. In 1918 673 of 1000 shares of the Gewerkschaft Braunsteinwerke Dr. Geier were acquired by Mannesmannröhren-Werke AG, Düsseldorf, followed by the purchase of another 27 shares in 1926. In 1939 all mining operations were mandated to Mannesmannröhren-Werke AG.
From 1945 to 1950 operations were controlled by the French military government, then management was mandated back to Mannesmann AG. In 1952 the Gewerkschaft Braunsteinwerke Dr. Geier was incorporated into the Gewerkschaft Mannesmann, Düsseldorf. The remaining mines Amalienhöhe, Elisenhöhe and Heerberg were modernized and extended. In the mid of the 1950s the exhaustion of the ore reserves became evident and in 1954 mining of the huge dolomite reserves started. Since 1964 a part of the dolomite was processed to dolomite sinter in rotary furnaces. The products were transported railway-bound via the Rheinstollen gallery to the shipping facility north of Bingen. During these years the mine increasingly suffered from high production costs compared to open pit dolomite mines and finally was not able to compete on the market so in 1971 the mine was closed. In total about 6.4 million tonnes Fe-Mn ore and about 2.5 million tonnes of dolomite had been recovered.
The surface installations of the Straubenschacht site are worth to be specially mentioned. The ensemble is considered to be a most important monument of mining related architecture in Germany. The impressive neo-baroque style site was planned by Markwort & Seibert from Darmstadt. Unfortunately the buildings partly are in a very bad shape today and one can only hope that there will be strong efforts to conserve and restore this outstanding cultural heritage in the near future.
References
References:
M. Berghäuser (2009): Rhodochrosit und seine Begleitmineralien aus der Grube "Dr.Geier" im Hunsrück. - Lapis, Vol. 34, Nr.3, 13-19.
H. Bottke (1969): Die Eisenmanganerze der Grube Dr. Geier bei Bingen/Rhein als Verwitterungsbildungen des Mangans vom Typ Lindener Mark. - Mineralium Deposita, Vol. 4, Nr 4, 355-367.
O. Ermann (1951): Die Eisen- und Manganerzlagerstätten des östlichen Hunsrücks (im Gebiete von Stromberg-Bingerbrück). - Der Aufschluss, Vol.2, Nr.6, 85-87.
K.Klemp (1987): Grube Dr. Geier - Monument des deutschen Erzbergbaus. - Biebertal, 1987.
W. Rosenberger (1971): Beschreibung rheinland-pfälzischer Bergamtsbezirke. - Vol. 3, Bad Marienberg 1971.
A. Vierschilling (1910): Die Eisen- und Manganerzlagerstätten im Hunsrück und Soonwald. - Z. Prakt. Geol. 18, 393-431.
[Roger Lang 2009]
Rhodochrosite
Germany
Reinland-Palatinate, Siegerland, Herdorf, Wolf Mine.
Specimens
Rhodochrosite from the Wolf mine is probably one of the best known mineral species from Germany in the world. The specimens from there are considered to be the best of Europe and they are present in museums and collections worldwide. Finds were restricted to the active mining period so nowadays specimens from there are highly sought and the prices high. The rhodochrosite varies in colour from salmon pinkish to raspberry pink or orange-reddish to brownish. Typically it is associated with limonitic matrix where it forms crystals and aggregates in vugs of the ore. The habit varies from single millet-seed shaped crystals to star or hedgehog shaped aggregates of those, barrel and cone shaped crystals as well as sheave-like aggregates. Most of the crystals are built by numerous small steep scalenohedral subindividues. The crystals reach up to about 2 cm size, larger crystals have been extremely rare. The majority of the crystallized samples show crystal sizes from a few mm to about 1 cm. Also botroydal and spherical aggregates and coatings were common. The aggregates often show a 'raspberry' like habit ('Himbeerspat' - raspberry spar - Breithaupt, 1832). The most beautiful specimens are of a deep orange-pink colour, they are translucent and provide a great contrast to the limonite matrix. Combo specimens of rhodochrosite with malachite-coated crystals of native copper (reaching sizes of up to about 3 cm) on matrix are the most interesting association of the Wolf mine. The best and richest specimens were found in a zone around the 350 m level.
Geology
The Wolf mine belongs to the Siegerland siderite district where mining goes back to celtic times. The ore of this district is primarily of sideritic type with more or less developed oxidation zones where limonite/goethite is prevalent. Also Pb, Zn, Cu and Ag as well as Co and Ni minerals occurred frequently - especially at the upper levels - and mostly have been mined at the beginning of modern mining. Mineralization is of hydrothermal origin and developed as veins in Devonian sedimentary rocks (shales, sand- and siltstone) of the Rheinisches Schiefergebirge. The Wolf mine was characterized by a deeply developed oxidation zone (to a depth of almost 400 m), probably due to the influence of the intrusion of tertiary basaltic melts in the neighborhood which provided thermal energy and fluid flow favouring the alteration of the siderite veins. The rhodochrosite finds were restricted to the limonitic ores of the oxidation zone. Towards depth the ore became sideritic with quartz gangue and towards the roots of the veins the quartz content increased.
History
The Wolf mine is one of the younger mines of the district. Mining started about 1870 when limonite ore was extracted via adits. In 1890 the Reifenrath brothers from Neunkirchen acquired the mine and sank a shaft. Having reached a depth of 300 m the mine was sold in 1917 to Krupp, Essen and modernized by the installation of new steam machines for haulage. The water pumps were fitted with electric power supply. Consequently the extraction tonnage increased to 4,000 - 5,000 tonnes per month. During the 1920s 200 to 250 miners worked at the mine. In 1925 the mining stopped due to economic reasons. The surface installations were demolished and the mine was flooded. 10 years later the reopening was prepared by pumping out the mine and the building of new surface installations including an electric hauling machine and a cableway to transport the ore to the central processing plant at the Füsseberg mine in Daaden-Biersorf. On 1st of may 1937 the mine was then reopened again. With an extraction of 84,000 tonnes of ore the year 1944 marks the best yield in the history of the mine. But in 1945 the mine closed again due to World War II impact and the mine was flooded again. In 1953/54 the last mining period at the Wolf mine started: it then was consolidated with the San Fernando, Friedrich-Wilhelm, Füsseberg and Große Burg mines to a combined mining complex. The mined ore was transported underground to the San Fernando mine and hauled and processed there. Finally in 1962 the mine was completely closed.
References
R. Bode (1980): Die Grube Wolf in Herdorf, Siegerland. - Emser Hefte 3, 6-35.
A. Hoffmann (1964): Beschreibung rheinland-pfälzischer Bergamtsbezirke - Band 1 Bergamtsbezirk Betzdorf. - Verlag Glückauf, Essen.
H.-G. Koch (1982): Erzväter - Berg- und Hüttenleute im Siegerland und Westerwald. - Verlag Gudrun Koch, Siegen.
W. Richartz (1979): Rhodochrosit von der Grube Wolf. - LAPIS, Vol. 4, Nr. 10, 12-16.
[Roger Lang 2009]
Rhodochrosite
Germany
Rhineland-Palatinate, Westerwald, Wied Iron Spar District, Altenkirchen, Bürdenbach, Louise Mine.
We need a German specialist to tell us about rhodochrosite from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Greece
Macedonia Department, Chalkidiki Prefecture, Cassandra Mine.
We need someone who know about Greek minerals to tell us about the specimens from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Japan
Hokkaido Island, Shiribeshi Province, Shakotan peninsula, Inakuraishi Mine.
It is obvious from what Alfredo Petrov tell us below that we have not even scratched the surface of what is available from this and other Kokkaido mines and that the pictures above are of what are almost certainly rather poor specimens.
Several big mines in southwestern Hokkaido worked hydrothermal rhodochrosite veins traversing Tertiary (mainly Miocene) sediments and volcanic agglomerates. As pink rhombohedra to several cm (but commonly only up to 1cm) in cavities and as gangue in sphalerite-chalcopyrite-pyrite ore at the
Oue (or O'e) mine; the Senzai rhodochrosite vein here, one of the longest in Japan with a strike of 1.5km in Tertiary sediments, was mined as Mn ore. Sometimes as beautiful banded masses of different tones of pink, alternating with sphalerite and pyrite bands. Light pink, lenticular rhombohedra to almost 2cm form crusts lining cavities in
en echelon rhodochrosite veins crossing Miocene propylite at the
Inakuraishi mine; also as compact massive crusts to 5cm thick formed of bands from 0.3 to 10mm wide, varying from pinkish white to deep pink, associated with pyrite and sphalerite; also as pink stalactites to 15cm long and 2cm diameter, looking very similar to the famous Argentine ones but a lighter pink color. Inakuraishi was the largest Mn deposit in Japan (1944 production 72,000 tons ore @ 27% Mn); the largest vein measured 900m, x 5m thick, with known dip of over 250m. After metal mining ceased, there was some minor commercial production of rhodochrosite for ornamental use. In the
Yakumo silver mine as rhombic crystals up to several cm in rhodochrosite-alabandite-sphalerite-galena ore, with pyrite, marcasite, pyrrhotine, pyrargyrite and tetrahedrite-tennantite; rhodochrosite veins in Tertiary rock were also mined here as Mn ore. As at the Inakuraishi mine, there was mining here for ornamental rhodochrosite after metal production had ended, and there were beautifully banded structures of fine light pink rhodochrosite alternating with sphalerite-pyrite-galena bands. Another big producer of vein rhodochrosite in southwestern Hokkaido was the
Johkoku mine (type locality for jokokuite) which yielded 105,652 tons of crude rhodochrosite in one year (1958)! The
Imai-Ishizaki mine and the
Toyoha mine (type locality for toyohaite) were big rhodochrosite ore producers too.
Most Hokkaido rhodochrosite specimens in dealer stock are labelled as being from the Inakuraishi mine and to be "old" specimens. I suspect that quite a few "Inakuraishi" specimens might be from other Hokkaido mines, as the parageneses are very similar. The best quality specimens came out after mining for manganese ore had ceased and the mines were later being worked on a small scale just for specimens and for lapidary rough, ie well after the end of WWII, and mostly the 1980s. The truly "old" specimens were not nearly as good. Also, since most classic japanese minerals are indeed "old", and very hard to get nowadays, they tend to be priced high by dealers, and rightfully so; but rhodochrosites, however, were mined in relatively large quantity and are still readily available in Japan, so the prices asked for such specimens outside Japan are probably rather too high.
[Alfredo Petrov, April 2009]
Rhodochrosite
Japan
Honshu Island, Tohoku Region, Aomori Prefecture, Naka-Tsugaru-gun, Nishimeya-mura, Oppu Mine.
We need to have an person knowledgeable about Japanese minerals tell us about the rhodochrosites from this old and famous mine. This mine is better known for its massive/botryoidal forms of rhodochrosite than its crystals.
[Rock Currier, 2 January 2009]
Rhodochrosite
Japan
Honshu Island, Kanto Region, Tochigi, Kanuma
We need someone to tell us about the rhodochrosite from this locality.
Rhodochrosite
Kazakhstan
Zhezqazghan Oblysy (Dzezkazgan Oblast'; Dzhezkazgan Oblast'; Djezkazgan Oblast'; Jezkazgan Oblast'), Balqash (Balkhash; Karatas; Prebalkhashie) Region, Kounrad Massif
We need someone to tell us about the rhodochrosite from this locality. Is this the same locality as the Kazakhstan rhodochrosite we show below?
Rhodochrosite
Kazakhstan
Atasu-Karazhal-Zhayrem area, Ushkatan (Ushkatyn) deposit.
We need someone to tell us something about the rhodochrosites from the Ushkatan deposit.
[Rock Currier, 2 January 2009]
Rhodochrosite
Kosovo
Sysert' district, Tumet river, Kosovo, Kosovska Mitrovica, Terpča valley, Terpča complex.
We need someone to tell us about the rhodochrosite from Trepča.
[Rock Currier, 2 January 2009]
Rhodochrosite
Mexico
Chihuahua, Santa Eulalia District, Potosi Mine
Rhodocrosite specimens were found between the 10th and 11th levels of the Potosi mine in abundant vugs. The habits are medium-pink botyroidal masses, bright pink rhombohedra and rarer blood red crystals. Brownish elongated scalenohedral crystals to 8cm "cathedral rhodochrosite" were found circa 1987. They are not very common. Of all the times I have bought specimens at the mine (five or six times) I was never offered a good specimen of rhodochrosite.
[Rock Currier, 2 January 2009]
Rhodochrosite
Mexico
Guerro, Mun. de Taxco, Taxco de Alarcón (Taxco), Remedios Mine.
We need someone to tell us about the rhodochrosite from the Remedios Mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Mexico
Sonora, Mun. de Cananea, Cananea
We need someone to tell us about the Rhodochrosites from Cananea
Rhodochrosite
Peru
Ancash Department, Bolognesi Province, Pachapaqui District.
The Pachiqaqui district has produced a wide selection of pink to pale pink rhodochrosite specimens. Some of them are so pale that I wonder if they are even rhodochrosite. Some of them are quite striking. Over the years probably some thousands of specimens have been produced and sometimes in Lima you could buy them by the Kg.
[Rock Currier, 2 January 2009]
Rhodochrosite
Peru
Ancash Department, Pallasca Province, Pasto Bueno District, Pasto Bueno Mine.
Pasto Bueno is a little company town where they mine tungsten and the mine was productive prior to World War II and mining is still going on. Until about 1960 almost all of the specimens produced were run through the mill. The little mine known as Huayllapon, is located some distance above the town and the main tungsten mine. This the mine that has produced most of the Rhodochrosites and Hübnerite specimens that the locality is famous for. The good Rhodochrosites from this mine were never abundant and I would estimate that there less than 100 good specimens were produced. They were usually associated with quartz and very rarely hübnerite though I don't think I ever saw a really good Rhodochrosite/Hübnerite combination. When the mine started to produce good rhodochrosite specimens, they rivaled the best in the world, but later the Sweet Home mine was reopened by Brian Lees and the ones he produced put the Peruvian rhodochrosites in the shade. The first really good rhodochrosite that came out of the camp was sold to an American dealer for about $15 by the company geologist mostly because he thought it was not rhodochrosite because it did not bubble when he put acid on it. Needless to say it was sold at a substantial mark up. In a country of remote mines, this was very remote and not a healthy place to work or visit. A friend of mine got hepatitis while visiting the camp and the camp doctor told me that there was a 75% incidence of tuberculosis and a 120% incidence of hepatitis in the camp. The mine is so high up ~15000 feet that the mine managers house was the lowest one in the camp.
[Rock Currier, 2 January 2009]
Rhodochrosite
Peru
Junín Departmen, Yauli Province, Morococha District, Manuelita Mine.
This mine has never produced many good rhodochrosites, but over a period of perhaps 20 years there has been a steady trickle of them coming out. All total I may have made about 15 trips to Peru to buy minerals for my business and don't ever recall being offered a quantity of rhodochrosite specimens from this mine. I was once able to buy a very nice small specimen once on the street from a runner, and that was about it.
[Rock Currier, 2 January 2009]
Rhodochrosite
Peru
Lima Department, Oyon Province, Uchucchacua Mine
The Uchucchacua Mine is a silver and base metal at an altitude of about 14 thousand feet like most of the miners n Peru. These matrix on these specimens is particularly difficult to trim and they always seem to break perpendicular to the surface of the specimen where the crystals are located and the matrix is very tough. You have to use a diamond saw to trim them properly. Because of the difficulty of trimming, many specimens from this locality have the rhodochrosite crystals glued back on the matrix. The mine has produced thousands of specimens and probably several hundred good ones, but the good ones were always hard to get.
[Rock Currier 2009]
Rhodochrosite
Peru
Pasco Department, San Jose de Huayllay District, Huaron Mining District, Huaron Mines.
Rhodochrosite specimens from the Huaron mines are quite rare. I have purchased hundreds of pounds of specimens from this mine over the years and there was not a single decent rhodochrosite among them and in fact I don't ever remember a single rhodochrosite in all those specimens. Huaron is much better known for its little prismatic quartz crystals associated with pyrite crystals.
[Rock Currier, 2 January 2009]
Rhodochrosite
Romania
Hunedoara Co. Sacarîmb (Sãcãrâmb; Szekerembe; Nagyág)
Rhodochrosite
Roumania
Maramures Co. Baia Sprie (Felsöbánya).
We need someone to tell us something about rhodochrosite from Felsöbánya.
[Rock Currier, 2 January 2009]
Rhodochrosite
Romania
Maramures Co., Cavnic
We need someone to tell us something about the rhodochrosites from Cavnic. It would appear that most of the good specimens come from the Boldut Mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
Slovakia
Bystrica Region
We need someone to tell us about the rhodochrosites from this locality.
[Rock Currier, 2 January 2009]
Rhodochrosite
South Africa, Republic of.
Northern Cape Province, Kalahari Manganese fields.
There are a number of manganese mines in the Lalahari Manganese fields and the specimens pictured above are probably mostly from Wessels and N'Chwaning mines. Below are more pictures of specimens from these mines. We need an expert on these deposits to step up and clarify which kinds of rhodochrosite specimens come from each of the mines.
[Rock Currier, 2 January 2009]
Rhodochrosite
South Africa, Republic of
Northern Cape Province, Kalahari manganese fields, Hotazel mine
We need someone to tell us about the rhodochrosite from the Hotazel mine.
Rhocochrosite
South Africa, Republic of.
Northern Cape Province, Kalahari manganese fields, Hotazel, Wessels Mine (Wessel's Mine).
We need someone to tell us more about the rhodochrosites from the Wessels Mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
South Africa, Republic of.
Northern Cape Province, Kalahari manganese fields, N'Chwaning Mines.
Probably most of the best specimens of rhodochrosite from Hotazel came from this mine. Prosper Williams a mineral dealer was the first to bring out specimens from this area and I remember wanting one badly but they were just too expensive for me to buy. Later better ones were found at the N'chwaning and I got a crack at some of those, but I never got a great one. Probably more than 1000 specimens have been produced, but probably less ten great ones. One of the great ones is know as the "snail" and belongs to Bill Larson of Fallbrook, California. Some day I may tell the story of how he got it.
[Rock Currier, 2 January 2009]
Rhodochrosite
Ukraine
Crimea Oblast', Kerch peninsula.
I thought these were rather remarkable. The Kertch peninsula is perhaps better know for its specimens of the phosphate minerals metavivianite and anapaite which are sometimes also found growing inside fossil sea shells
[Rock Currier, 2 January 2009]
Rhodochrosite
United Kingdom
England, Cornwall, St. Just District, Botallack - Pendeen Area, St. Just District, Botallack Mine
This is a classic old Cornish tin mine dramatically poised on the scenic cliffs above the sea. The mine drove galleries out under the sea and there are stories that the miners could hear the waved breaking on the rocks above them and the water seeping into the mine would taste of salt. It never produced specimens you would kill your grandmother for and probably is famous because it famous. Better know or its cassiterite and axinite specimens one generally does not think of it producing rhodochrosite specimens, but it did sparingly.
Rhodochrosite
UK
England, Sommerset, Long Ashton, Durnford Quarry
"About the find .... one of my best collecting days in the UK !! Found memories ....
It was on March 24th 2007 during a Russell Society field trip, and i believe about 4/5 of us were lucky enough on the day. One week after there was not much left i heard and rest went probably to the crusher. I would not count the find in flats, but would say about 15 - 20 of good/top quality were collected on the day (kept 4 and gave a few - sic !!). Some had also Wulfenite but not on the specimen i collected, but i believe the one uploaded was the largest Rhodo. cavity found."
1. The Durnford Quarry is a limestone quarry and there were a few small wulfenite crystals found. Emmanuel reports at least one orange crystal of about 8mm was found.
1. Emmanuel Bravais, email communication 2009.
The material from Durnford Quarry is largely rhodochrosite. I ran X-ray powder diffraction (XRD) and Energy dispersive X-ray analysis (EDX/EDS) on material from the original find (2007) and several XRD runs produced perfect matches with the patterns for rhodochrosite. Questions were raised over what the true manganese content was, so I ran the XRD powder by EDS on a an SEM stub in 2008 and it came back with the ratio 10.47-11.54% Mn: 1.38-1.70 % Ca: 0.46-0.55 % Mg: no detectable Fe. Obviously this is semi-quantitative as you cannot measure the carbonate component, but clearly it is manganese-dominant. The locality was kept vague, due to issues regarding people collecting there without permission, but most of the new specimens sold during 2007/2008 as Merehead Quarry, are actually from Durnford Quarry. Merehead Quarry as noted earlier did produce pink samples, but most have turned out to be manganese-rich calcite.
[Tom Cotterell, Amgueddfa Cymru - National Museum Wales, email communication 2009]
Rhodochrosite
USA
Clear Creek Co., Dailey District (Jones Pass District)
We need someone to tell us about the rhodochrosite from this locality.
Rhodochrosite
USA
Colorado, Eagle Co., Gillman District, Gillman, Eagle Mine.
A cavity in pyrite-sphalerite ores was discovered on the 20 level of the Rocky Point orebody in 1976. The crystals are pale to deep rose-pink in color (less than 1% iron) disc shaped and range in size from 0.5 to 2.5cm.
Rhodochrosite
USA
Colorado, Gilpin Co. Central City District, Moose Mine.
Numerous crystals and cleavage fragments of dark red rhodochrosite were found during mining and on the dumps. Red rhombohedral crystals to 7.5cm were found in operations in the 1980's on the 150 foot level.
Rhodochrosite
USA
Colorado, Hinsdale Co., Park District (Sherman District), Cinnamon Pass, Champion Mine
We need someone to tell us about the Rhodochrosite specimens from the Champion Mine.
Rhodochrosite
USA
Colorado, Lake Co., Climax District, Climax Mine.
Climax is a big molybdenum mine at about 11,000 feet altitude and though not know for many good specimens, once in a while the miners encountered rhodochrosite specimens, but they were not common. The rhombohedral crystals are a rich red color and occur as single crystals or intergrown groups to 5cm. Most of the crystals were obtained from underground areas, although the majority of the mining was done in the open pit.
Rhodochrosite
USA
Colorado, Lake County, Leadville District, Alicante, John Reed Mine.
Red to deep rose rhombohedrons to 2.5cm although the better specimens are of the order of 1cm. Some of the rhodochrosite from this mine has been facetted (a 8.4 carat stone in the Denver museum collection).
Rhodochrosite
USA
Colorado, Ouray Co., Daniel Bonanza Mine.
We need someone to tell us something more about the rhodochrosite specimens from the Daniel Bonanza Mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
USA
Colorado, Ouray Co., Ouray District, Ouray, Bear Creek Canyon, Grizzly Bear Mine
Locality photos one two.
Grizzly Bear Mine produced translucent rose-red rhombohedra. Pink crystals on green quartz (chlorite included) were actually found in the Zanett tunnel (driven toward the Grizzly Bear vein).
[Rock Currier, 2 January 2009]
Rhodochrosite
USA
Colorado, Park Co., Alma District, Mount Bross, Sweet Home Mine.
The Sweet Home Mine has produced more fine rhodochrosites than another mine in the world. It also has the distinction of being one of the few mines that has ever been able to support a mining operation from the sale of specimens alone. Several hundred fine rhodochrosites specimens have been produced and some of them have sold for more than a million dollars I think one of them may have been sold for several million dollars. The story about these specimens and the mining of them is interesting to read. Brian Lees of the Collectors edge was the driving force behind the project and he was meticulous in the care with which the specimens were extracted and developed new tools and methods to do it successfully. It was a small mining operation but a very careful one. A normal mining operations would have destroyed most of the specimens.
1
1. Mineralogical Record, Sweet Home Mine Issue, July-August, 1998, Vol. 29 No. 4.
[Rock Currier, 2 January 2009]
Rhodochrosite
USA
Colorado, San Juan Co. Silverton District, Howardsville, American Tunnel Mine.
At one time the rhodochrosite specimens from this mine were abundant. Thousand of them were produced. The best of them were associated with white quartz and somewhat rounded subdued green fluorite crystals. We could use some help here describing the rhodochrosite specimens from this mine.
[Rock Currier, 2 January 2009]
Rhodochrosite
USA
Montana, Silver Bow Co., Butte District, Butte.
Butte Montana has produced a surprising variety of rhodochrosite specimens though few of them are really red. We could use someone to help in describing the rhodochrosite specimens from this locality.
[Rock Currier, 2 January 2009]
Rhodochrosite
USA
New Jersey, Sussex Co., Franklin Mining District, New Jersey
We need someone to tell us about Rhodochrosite specimens from Franklin
Rhodochrosite
USA
North Carolina, Cleveland Co., Kings Mountain District, Foote Lithium Co. Mine
We need someone to tell us about Rhodochrosite specimens from the Foote Mine
Rhodochrosit
USA
Utah, Utah Co., East Tintic Mts, East Tintic District, Burgin Mine,
Rhodochrosite
USA
Wisconson, Iron Co., Montreal, Montreal Mine (Ottawa; 33 Company Mine; Trimble; Odanah; Moore; Jupiter; Bourne; Sec. 33 Mine)
Found in the lower levels of the Montreal Mine (38th level of #5 shaft). Crystals are light pink in color and occur as rhombohedroms or better as radiating groups of thin prismatic crystals to 3cm in length on manganite.
Do you know of other rhodochrosite localities that should be included here? We would like to hear about them.
Rock Currier
Crystals not pistols.
Edited 149 time(s). Last edit at 11/06/2009 10:45PM by Rock Currier.
