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Magnetite

Posted by Rock Currier  
avatar Magnetite
November 11, 2010 12:30PM
Click here to view Best Minerals M, click here to view and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.


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?



MagnetiteFe2+Fe3+2O4 Isometric

Magnetite on Albite, 5cm tall
Magnetite on Albite, Cerro Huañaquino, Potosí Department, Bolivia 5cm tall
The name magnetite is apparently derived from the locality Magnesia, which borders on Macedonia. The ancient writers, Pliny and Nickander attribute the name to a person? named Magnes who on taking his herds to pasture found that the nails of his shoes and the iron ferrule of his staff stuck to the ground.

So far Mindat lists more than 9700 localities for magnetite and undoubtedly there are many more. Magnetite is one of the most abundant and commonly found oxides and is found under diverse geological conditions and sometimes in sufficient quantity to comprise an ore of iron. Magnetite is commonly found as grains in igneous rocks but most abundantly in the ferromagnesian types and at times as large segregated masses. Often these contain a lot of titanium in their composition due mostly to illmenite. Magnetite forms in the same conditions which form hematite and is usually if not always formed under conditions of high temperature. It it is found in the fusion crusts of meteorites and as dendritic forms in the mica of many localities and may be of secondary origin. It is also noted as a furnace product in slags and in sintered hematite ores. Brick, vitreous clay ware, and porcelain acquire a permanent magnetization parallel to the earths's magnetic field if magnetite crystals form during the firing. The largest deposits of magnetite are found in lens shaped masses in northern Sweden in Archaean rocks

A strong indicator that you may have magnetite is to see if it is attracted by a magnet and by checking its streak which is black. Maghemite, another strongly magnetic iron oxide, is brown to bluish black and can easily be confused with magnetite. However, unlike magnetite, it transmits light in thin splinters and has a brown streak. Hematite for which Magnetite is occasionally mistaken has a dark red streak and is not attracted by a magnet. Heating magnetite to 550 degrees C however alters the mineral to hematite and causes loss of its magnetic property. Magnetite alters to limonite and to hematite. Magnetite pseudomorphs after pyrite, chlorite minerals, anatase, talc, dolomite, chalcopyrite, siderite, and serpentine are known. Presumably all of these may be found not completely altered and containing the originative mineral and magnetite as well. So if you get a reaction to a magnet from a mineral, it may also not be a pure mineral, but partly magnetite. At some few localities, magnetite possesses polarity and this magnetite is given the variety name of lodestone. This means that the magnetite will act as a natural magnet. This natural magnetism can sometimes be enhanced by placing it in a strong magnetic field.

Magnetite crystals are most commonly found as octahedrons, but is also found in dodecahedrons with striated faces and more rarely as cubes. Sometimes octahedral forms of magnetite are altered to hematite and this is common enough that they are given the varietal name of martite (hematite, var. martite). Sometimes pure masses of twinned magnetite are found and when broken along its parting planes forms crystals that are sometimes mistaken for crystals of magnetite but are in reality just parting forms of twinned magnetite. The magnetite from Port Henry, New York example these. The cleavage of untwinned magnetite is not distinct.

The literature on magnetite and hematite is extensive and not something we want to go into here. Much of what is above was taken from Dana's/Ford text and Dana's system 7th edition, V1, P698-705 which has a nice summary of information about magnetite.

Historically, the most sought after crystals by collectors were perhaps those from Switzerland. Recently however the new find of good octahedral magnetites from Cerro Huañaquino, Bolivia and especially the new brilliant cubic magnetites from Balmat, New York, USA have displaced the Swiss specimens as the most desired. However, you can look at good examples of all of these and more in the picture gallery below and make up your own mind.



MagnetiteAfghanistanNangarhar Province (Ningarhar Province), Khogyani, Marki KhelNangarhar Province (Ningarhar Province), Speen Ghar

Magnetite3.7cm tall
Magnetite 2.1cm tall

The one on the left above is from Marki Khel, and the one on the right from Speen Ghar. It would appear that both of these specimens are very likely from the same locality and at the very least we hope someone can help sort out what these two locality names represent when it comes to the specimens from them.


Magnetite?!!!ArgentinaMendoza, Altiplano de Payún Matru, Payún volcano

Magnetite?!!! 4.5cm wide
Magnetite?!!! 10.3cm tall

Specimens like this from Payún volcano are usually labeled Hematite after Magnetite and many more and much better examples are shown under Hematite in the Mindat Gallery and the Best Minerals Hematite article. It is possible that these specimens have still retained their magnetic character and that is why they are currently labeled magnetite. It is also possible, and perhaps even likely that these specimens have been mislabeled and are really now Hematite. Many collectors and some dealers really don't pay much attention to the accuracy of the labels they receive with their specimens or generate themselves and don't take the time to run even the simplest of tests on their specimens to determine if perhaps the labels may be in error. In fact they don't even know how. As time passes and you learn more and gain more experience you will see more and more errors on labels and will learn to look specimen labels with a more critical and analytical eye. We need more of this kind of person here on mindat to help clean up the mistakes and errors that exist here on Mindat.
"Although these specimens are usually labelled "Payun" or "Payun Matru" volcano, this is actually in a rather extensive volcanic field with dozens of vents, and exactly which fissures these crystals came from has understandably not been revealed by the prospectors who dig them, and there are at least two localities for them in this area, so "Payun Matru region" or just "Altiplano de Payun Matru" might be a more honest locality designation, leaving off the volcano name. As is obvious from the crystal habits, these started out as magnetite, although the majority have oxidised to hematite and should now be labelled "hematite pseudomorphs after magnetite". A minority are still magnetite, or only partially replaced. Magnetite and hematite crystals, often skeletal, deposited from the gas phase in volcanic fumaroles by hydrolysis of iron chloride vapour are fairly common in high-temperature volcanic fumaroles worldwide, but these argentine examples are by far the largest and finest fumarolic magnetites known." - Alfredo Petrov, 2010.


MagnetiteAustraliaNorthern Territory, Harts Ranges (Hartz Ranges), Mud Tank

Magnetite 3cm wide



This is a popular collecting spot, mostly for large zircon crystals, in a carbonatite. It was being mined for Vermiculite recntly, with collectors allowed to fossick on the dumps still. The magnetite crystals can be large, but are seldom completely intact.


MagnetiteAustraliaQueensland, Biggenden Shire, Biggenden Mine (Mount Biggenden Mine; Biggenden Gold And Bismuth Mine; Mount Biggenden Bismuth Mine; Mount Biggenden Magnetite Mine; Biggenden Quarry)

Magnetite 9cm wide



This site was a large magnetite mine, in a skarn deposit. It was a popular spot for collecting until the mine closed some (20?) yrs ago, and specimens are rarely seen now.


MagnetiteAustraliaSouth Australia, Flinders Ranges, North Flinders Ranges, Arkaroola area, Sitting Bull area

Magnetite 5.4cm wide



A popular collecting area with various small iron, copper, fluorite and uranium deposits related to granite intrusions, but good specimens are rarely seen.


MagnetiteAustraliaTasmania, Hampshire district, Kara Mines, Kara #1 Pit

Magnetite, Andradite etc 15cm wide



An operating open-cut mine, located 40 km south of Burnie in northwestern Tasmania, producing magnetite and minor scheelite. It is the only presently operating mine in a series of related skarn deposits associated with Devonian granites intruding Ordovician limestones. The pit contains a zoned magnetite-andradite-hedenbergite-vesuvianite-epidote skarn, which contains minor scheelite and molybdenite and calcite veins with various Cu, Pb, As, Zn, Bi sulphides, fluorite and some Be minerals. Famous for excellent andradite specimens and many other interesting minerals. Magnetite is very common, often in well formed dodecahedral crystals, to about 5cm, but are typically a little dull in lustre. They may be coated in other crystallised minerals, including bavenite, fluorite, calcite, andradite, epidote, tremolite and helvite-danalite.



MagnetiteAustriaSalzburg, Hohe Tauern Mts, Stubach valley, Totenkopf Mt. (incl. Lower Riffl glacier)

Magnetite & Actinolite ~9cm wide




MagnetiteAustriaTyrol, North Tyrol, Ziller valley, Schlegeis valley (Schlegeisgrund), Furtschaglkar

Magnetite 16.5cm wide




MagnetiteAzerbaijanDaşkəsən (Daskasan; Dashkyasan) District, Dashkesan, Dashkesan (Dashkezan) Co-Fe deposit

Magnetite 8cm tall
Magnetite 10cm center


Magnetite & Calcite 5.3cm wide
Magnetite & Calcite 11.9cm wide


Magnetite 10cm tall
Magnetite 5cm tall


Magnetite & Fluorapatite 6.0cm
Magnetite 12cm wide


MagnetiteBoliviaPotosí Department, Cerro Huañaquino

Magnetite 3.3cm wide
Magnetite 6cm wide


Magnetite 5.5cm tall
Magnetite 12.5cm tall


Magnetite 5cm tall
Magnetite 6.3cm wide


Magnetite 8.6cm wide
Magnetite 8.4cm wide


Magnetite 4.1cm wide
Magnetite 12.3cm wide


Magnetite 6cm wide
Magnetite 5cm wide


Magnetite 10.4cm tall
Magnetite 13.1cm wide

As you head north out of Potosi, the main highway for a distance passes by Cerro Huañaquino. If you look up at that point you can see little prospects scratched on the side of the mountain a few hundred feet up, and this is the locality that has produced all the recent specimens of Magnetite from Bolivia. Several thousand of them have been produced and sold to the collector market. Some of the specimens are surprisingly good and may rank among the best Magnetites found anywhere. On many specimens the magnetite crystals are growing on tiny crystals of albite.


MagnetiteBrazilMinas Gerais, Jequitinhonha valley, Diamantina\

Magnetite 4.2cm wide
Magnetite 4.8cm wide


MagnetiteCanadaNova Scotia, Annapolis Co., Hampton

Magnetite 3.5cm wide



John Sinkankas notes in his Mineralogy that small, beautifully crystallized magnetite crystals occur in the Triassic trap rocks of Kings and Annapolis counties.


MagnetiteCanadaNova Scotia, Kings Co., Bay of Fundy, Amethyst Cove (Captain Kidd's Cove)

Magnetite 3.1cm wide




MagnetiteCanadaOntario, Hastings Co., Bancroft District, Faraday Township

Magnetite ~6cm wide
Magnetite ~5cm tall.

John Sinkankas notes in his Mineralogy that a single crystal from this locality weighed in at more then 400 pounds.


MagnetiteChileAntofagasta Region, El Laco

Magnetite 12.9cm wide




MagnetiteCubaOriente Province, Firmeza District, Juragua Iron Co. Mines

Magnetite 4.5cm tall




MagnetiteCzech RepublicBohemia (Böhmen; Boehmen), Ústí Region, Krušné Hory Mts (Erzgebirge), Klášterec nad Ohří, Měděnec (Kupferberg)

Magnetite 6.5cm wide




MagnetiteFranceMidi-Pyrénées, Aveyron, Decazeville, Firmi, Puy de Wolf (Puech de Voll)

Magnetite on serpentine 8cm wide




MagnetiteGermanyBaden-Württemberg, Odenwald, Eberbach, Katzenbuckel Mt., Michelsberg Quarry

Magnetite 25cm wide



The Magnetite (Titanomagnetite) from Katzenbuckel are crystals up to 3cm but most of the crystals found were only a few mm. At this location the magnetite crystals are frequently oxidized to Maghemite. They are still magnetic, but the streak changes from black to brown. If etched with cold 30 % HCl this pseudomorphed crystals give a white residue of Leukoxene ( Anatase) while with the real Magnetite the black Ilmenite inclusions remains. The locality is of the European Province with unusual peralkaline dyke rocks. This location was first metioned by Leonhard in 1822 for Nepheline and is located about 35 km E of Heidelberg. With a very long list of papers until today. A milestone of petrography/ petrology research ( Rosenbusch). The quarries were operated from about 1900 to 1974, the locality is now a geotop. The crystals are not free standing but found covered by natrolite, but the crystals are easy to clean because of alteration of the rock. The magnetite specimens were abundant for a short time (1966 to 1973). Since that time collecting is almost impossible as the zone that was productive of the magnetite crystals is flooded. I think only a small number has been distributed, but one of the best magnetites in Germany. There are better specimens than the one pictured here



MagnetiteGermanyBavaria, Lower Bavaria, Bavarian Forest, Zwiesel, Bodenmais, Silberberg Mine

Magnetite 5cm wide




MagnetiteGermanyRhineland-Palatinate, Eifel Mts, Mendig

1.37mm Magnetite xl on matrix




MagnetiteGermanySaxony, Glauchau, Callenberg

Magnetite 10cm wide
Magnetite 11.1cm wide


MagnetiteItalyCampania, Naples Province, Somma-Vesuvius Complex, Monte Somma, Ercolano, San Vito, San Vito quarry

1.22mm Magnetite xl on Diopside
1.23mm Magnetite xl with Diopside


MagnetiteItalyLombardy, Sondrio Province, Malenco Valley

2.11mm group of Magnetite xls
Magnetite 4.5cm wide


MagnetiteItalyLombardy, Sondrio Province, Malenco Valley, Lanterna Valley

Magnetite 10cm tall




MagnetiteItalyLombardy, Sondrio Province, Malenco Valley, Lanterna Valley, Campo Franscia, Franscia Mine

1.7 mm Magnetite cluster
Magnetite on matrix 11 cm wide


MagnetiteItalyPiedmont, Torino Province, Canavese District, Chiusella Valley, Traversella, Traversella Mine

Magnetite 6.2cm wide
Magnetite ~8cm wide


MagnetiteItalyPiedmont, Torino Province, Canavese District, Léssolo, Cálea, Brosso Mine

Magnetite & Pyrite 16cm wide
Magnetite & Pyrite 6cm wide


Magnetite & Pyrite 12cm wide




MagnetiteJapanHonshu Island, Chubu region, Nagano prefecture, Kuryu mine

Magnetite FOV 4.2cm




MagnetiteMexicoChihuahua, Mun. de Aquiles Serdán, Santa Eulalia District

Magnetite on Quartz ~6cm tall




MagnetiteMexicoDurango, Mun. de Durango, Cerro de los Remedios, Victoria de Durango, Cerro de Mercado Mine

Magnetite & Fluorapatite ~8cm wide
Magnetite 5cm wide

The magnetites from this locality are not particularly outstanding, but when they occur with sharp yellow sometimes transparent apatite crystals, I must admit that I find I become more interested in them.


MagnetiteMoroccoMeknès-Tafilalet Region, Khénifra Province, High Atlas Mts, Tamazeght complex, Bou-Agrao Mt.

Magnetite 6.2cm wide
Magnetite 6.3cm wide


MagnetiteMorocco
Souss-Massa-Draâ Region, Ouarzazate Province, Tazenakht, Bou Azzer District, Bou Azzer

Magnetite 4cm wide




MagnetiteMozambique

Magnetite 42cm wide



The only locality we have for this specimen is Mozambique, but the thing is huge and a deposit that produces things like this must produce other note worthy specimens. I hope someone can eventually tell us more about this locality and its specimens. The crystals on this specimen must be nearly as big as your fist and the thing must weigh well over 100 pounds.


MagnetiteNamibiaErongo Region, Usakos and Omaruru Districts, Erongo Mountain

Magnetite 7.9cm wide




MagnetiteNorwayNordland, Hattfjelldal

Magnetite on matrix ~3cm wide




MagnetiteNorway Telemark, Porsgrunn, Mørje, Auen( Blue Pearl) Quarry

Magnetite 2,5cm
Hematite after Magnetite. 6,2 cm wide

Auen is one of the many larvikitie quarries in this area. Larvikite is quarried as a dimension stone and is widely used as countertops and claddings. The commercial grade larvikite consist predominantly of blue or black schillerizing feldspar.
The larvikite was formed as igneous plutons during Permian (+/- 300mill years ago) rifting in the Oslo graben in southeastern Norway. These igneous plutons are host to numerous alkaline pegmatites carrying many rare minerals.

The magnetite at Auen was found in one of these pegmatites in 1996. The actual pegmatite was severly altered, with a clay mineral, albite covered microcline and magnetite as main minerals. Small zircon, molybdenite sheets and a yellow, transparent mineral was present as accessory minerals. Most of the magnetite was partly altered to hematite
The magnetite crystals reached almost 10 cm across and often had quite complex crystal shapes. The best specimen I found was a 15cm wide cabinet specimen consisting of three intergrown magnetite crystals. This specimen is now on loan to Agder Naturmuseum in Kristiansand. The magnetite was abundant in this material, and several truck loads of material were available just after the pegmatite was exposed, and magnetite could still be found in the quarry a few years after the initial exposure of material.



MagnetitePakistanNorth-West Frontier Province, Mansehra District, Naran-Kaghan Valley, Sapat Gali (Soppat; Suppat; Sumpat; Sumput)

Magnetite & Forsterite (peridot) 2cm tall
Magnetite & Forsterite (peridot) 9cm wide


Magnetite & Forsterite (peridot) 3.8cm tall
Magnetite & Forsterite (peridot) 3.3cm tall


Magnetite & Forsterite (peridot) 6cm wide



Magnetite crystals growing with gem grade peridot crystals? Every collector would love to have one of these. But the association was not common and for every thousand peridot crystals there may have been one specimen with this association.


MagnetiteRussiaFar-Eastern Region, Primorskiy Kray, Olginsky District, Olga Bay

Magnetite ~9cm wide




MagnetiteRussiaNorthern Region, Murmanskaja Oblast', Kola Peninsula, Kovdor Massif, Kovdor Mine

Magnetite 7.5cm wide




MagnetiteRussiaNorthern Region, Murmanskaja Oblast', Kola Peninsula, Kovdor Massif, Zheleznyi Mine (Iron Mine)

Magnetite & Calcite 3.9cm tall




Magnetite
b>RussiaUrals Region, Southern Urals, Chelyabinsk Oblast', Zlatoust, Nazyamskie Mts, Akhmatovskaya Kop' (Achmatovsk Mine)

Magnetite & Clinochlore 11cm wide




MagnetiteSouth AfricaNorthern Cape Province, Aggeneys

Magnetite & Chalcopyrite 7cm wide




MagnetiteSpainExtremadura, Badajoz, Burguillos del Cerro, Milucha Mine

Magnetite 7.5cm tall
Magnetite 14cm wide
Magnetite 8.5cm wide


MagnetiteSwedenVärmland, Filipstad, Nordmark (Nordmarksberg)

Magnetite & Calcite 10cm wide




MagnetiteSwitzerlandWallis (Valais), Binn Valley

Magnetite & Adularia 2.7cm wide




MagnetiteSwitzerlandWallis (Valais), Binn Valley, Lercheltini (Lärcheltini) area

Magnetite 5cm wide
Magnetite ~7cm wide


Magnetite, xl on left ~4cm




MagnetiteUSA
Arkansas, Hot Spring Co., Magnet Cove, Perovskite Hill

Magnetite 2.6cm tall



At one time magnet cove was famous for specimens of massive magnetite specimens that acted as natural magnets. They were rated in quality by the size of the nails they could pick up. The 16 penny grade would pick up 16 penny nails and the ten penny quality would pick up the larger ten penny nails (those that sold ten for a penny). The most highly sought after material was the spike grade material that would actually pick up a small railway spike.



MagnetiteUSACalifornia, Fresno Co., Wright Mountain area, Christie Mine (Christi Mine; Christy Mine)

Magnetite & Dolomite 2.7cm tall




MagnetiteUSACalifornia, San Benito Co., Diablo Range, New Idria District

Magnetite on matrix 3.9cm wide




MagnetiteUSACalifornia, San Benito Co., Diablo Range, New Idria District, Santa Rita Mine (Union Carbide Nuclear; Santa Rita Asbestos Mine; Joe 5 pit; Joe 7-5 Mine)

Magnetite ~8cm wide




MagnetiteUSAIdaho, Lemhi Co., Spring Mountain District

Magnetite on Ludwigite 5.3cm wide
Magnetite 4.3cm wide


Magnetite 4.2cm tall




MagnetiteUSANew Jersey, Hudson Co., Secaucus, Laurel Hill (Snake Hill; Penetentiary Quarry

Magnetite 4cm wide
Magnetite 8.8cm wide


At Laurel Hill, magnetite veins are common. Perfect specimens are not easy to come by, due to weathering and brittleness. Good specimens are obtained, when vein walls are composed of soft chlorite. Excellent splendent crystals were observed suspended as individuals and groups in the mountain leather variety of actinolite. Their color coal-black; crystallizing as octahedrons or penetrating (spinel) twins; up to 3 cm on an edge and associated with albite, sphalerite, pyrite, bornite, chalcopyrite, allanite, epidote, orthoclase, and quartz.



MagnetiteUSANew Jersey, Sussex Co., Franklin Mining District, Sterling Hill

Magnetite ~15cm wide




MagnetiteUSANew Mexico, Grant Co., Fierro, Hanover-Fierro District, Continental No. 2 Mine

Magnetite 2.3cm wide




MagnetiteUSANew Mexico, Grant Co., Hanover-Fierro District, Republic Mine

Magnetite 5cm wide




MagnetiteUSANew Mexico, Socorro Co., Jones District

Magnetite 5cm wide




MagnetiteUSANew York, Essex Co., Port Henry

Magnetite 2.7cm wide
Magnetite xls, label is ~5cm wide


Magnetite, big xl is ~12cm
Magnetite, xl on right is ~4cm
Magnetite ~5cm wide

These were at one time quite common among collectors in the north eastern part of the United States, but now are seldom seen. The bottom three images show not terminated crystals of magnetite, but rather parting forms that have been broken from massive twinned magnetite.


MagnetiteUSANew York, Putnam Co., Southeast Township, Brewster, Tilly Foster mine

Magnetite & Clinochlore ~12cm wide
Magnetite 3cm wide

The magnetite and clinochlore specimen pictured above is about as good as this association gets from this mine.


MagnetiteUSANew York, St Lawrence Co., Balmat-Edwards Zinc District, Balmat

Magnetite 5.8cm wide
Magnetite 4.2cm wide


Magnetite 7.2cm wide
Magnetite 11.9cm wide


Magnetite 9.2cm wide
Magnetite 5.5cm wide

The magnetite specimens from this mine have been around for a few years, but because of their brilliance and relatively cubic shape, they have a new standard of quality that other localities find difficult to match. The best from this locality are truly world class for the species.


MagnetiteUSAPennsylvania, Berks Co., Morgantown, Grace Mine

Magnetite 5.5cm wide




MagnetiteUSAPennsylvania, Chester Co., Warwick Township, St. Peters, French Creek Mines

Magnetite 6.8cm wide


There are better specimens of magnetite than the one pictured here and we will add one or more of them as soon as possible.


MagnetiteUSAVermont, Windsor Co., Chester, Carlton Quarry (Carleton Quarry)

Magnetite ~7.5cm wide




Click here to view Best Minerals M, click here to view and here for Best Minerals A to Z and here for Fast Navigation of completed Best Minerals articles.

Rock Currier
Crystals not pistols.



Edited 32 time(s). Last edit at 03/26/2012 11:36AM by Rock Currier.
Re: Magnetite
November 29, 2010 03:48PM
    
Rock,

Please see below.

Olav


MagnetiteNorway Telemark, Porsgrunn, Mørje, Auen( Blue Pearl) Quarry

Magnetite 2,5cm
Hematite after Magnetite. 6,2 cm wide

Auen is one of the many larvikitie quarries in this area. Larvikite is quarried as a dimension stone and is widely used as countertops and claddings. The commercial grade larvikite consist predominantly of blue or black schillerizing feldspar.
The larvikite was formed as igneous plutons during Permian (+/- 300mill years ago) rifting in the Oslo graben in southeastern Norway. These igneous plutons are host to numerous alkaline pegmatites carrying many rare minerals.

The magnetite at Auen was found in one of these pegmatites in 1996. The actual pegmatite was severly altered, with a clay mineral, albite covered microcline and magnetite as main minerals. Small zircon, molybdenite sheets and a yellow, transparent mineral was present as accessory minerals. Most of the magnetite was partly altered to hematite
The magnetite crystals reached almost 10 cm across and often had quite complex crystal shapes. The best specimen I found was a 15cm wide cabinet specimen consisting of three intergrown magnetite crystals. This specimen is now on loan to Agder Naturmuseum in Kristiansand. The magnetite was abundant in this material, and several truck loads of material were available just after the pegmatite was exposed, and magnetite could still be found in the quarry a few years after the initial exposure of material.



Edited 2 time(s). Last edit at 11/29/2010 07:17PM by Rock Currier.
avatar Re: Magnetite
November 29, 2010 07:21PM
Olav,
I have made a few tweaks to the formatting of your suggested addition to the magnetite article. Click on the edit button at the bottom of your post and you can see the code adjustments that I made. Note that in the second image, the code string I changed the left to center which gives it a little space between the images. I also adjusted the pixel size a little to line the pictures up. It looks good now.

You are a moderator in the best minerals group, why don't you go ahead and copy the whole thing into the magnetite article in the appropriate place?

What do you want to work on next? or perhaps you are already working on something.

Rock Currier
Crystals not pistols.
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