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Hardness

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Hardness in which unit? 21:31, 30 May 2003 JidGom

Mohs scale of mineral hardness --Chris.urs-o (talk) 09:07, 4 May 2011 (UTC)[reply]

This article liked to by a NASA news website

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The Astronomy Picture of the Day (APOD) website article for 15 Dec. 2004 featuring a photograph from the Mars Spirit Rover included a link to this Wikipedia article. It can be found here: [1] - Fire Star 06:46, 17 Dec 2004 (UTC)

Goethite and lepidocrocite nomenclature

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Originally, the names lepidocrocite (now gamma-FeOOH) and goethite (now alpha-FeOOH) were switched from the current usage. This has caused me great confusion in the past; I am sure I am not the only one. It would be good if someone with more knowledge of the history of that switch than I could put a mention of that historical usage into this article, as well as the lepidocrocite article. SarahLawrence Scott (talk) 20:22, 7 March 2009 (UTC)[reply]

Iron content

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I can see that there all authors have different types of iron content for Goethite, Magnetite, Hematite and Siderite. Do anyone know about any international classification standards on the different types? Or do anyone know about a book that has stated what the most common iron content is for the different types? Krosgaard (talk) 07:23, 24 June 2010 (UTC)[reply]

Type locality

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Changed the "first described..." from Minnesota to Germany per Mindat.org and others. The Webmineral site says Minnesota, but then defers to Mindat location data ... seems an error perchance. Plus the Mesabi Range was rather unknown in 1806. Vsmith (talk) 03:00, 4 May 2011 (UTC)[reply]

Addenda, the Webmin site simply states Locality: Mesabi district, Minnesota, USA. Link to MinDat.org Location Data. and doesn't say "first described...". So seems too much was read into that (error in reading), and yes it does occur in the Mesabi iron ores. Vsmith (talk) 03:27, 4 May 2011 (UTC)[reply]
Well duh ... just took a scan of the article history and found the party who made that reading error, 'twas yours truly back in Feb 06 ... Thanks to User:Dankarl for asking about this on a talk page on my watchlist! Sorry 'bout that folks ... Vsmith (talk) 03:40, 4 May 2011 (UTC)[reply]

Iridensence

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I think the article should note and have an image of geothite's extreme iridescence. None of the current pictures really show samples with this properity, but those that do have a very large amount of it, some to the same level as peacock or, or even more so, like bismuth. 69.132.69.87 (talk) 19:55, 16 December 2011 (UTC)[reply]

Limpet teeth

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Should the following article prove more than spurious pop-sci, perhaps it should be mentioned? http://www.sciencealert.com/scientists-discover-the-strongest-known-natural-material-in-the-world Ernest Ruger (talk) 22:31, 19 February 2015 (UTC)[reply]

Look again - at the end of the Prevalence section. Vsmith (talk) 04:08, 20 February 2015 (UTC)[reply]

Slight contradiction.

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Abstract: Goethite is one of the most ubiquitous minerals on the Earth’s surface and it is also a significant mineral in economic deposits such as iron ore. Goethite was named in 1806 after the German poet, philosopher and naturalist Johann von Goethe. In iron ore, the two main goethite subtypes are ochreous and vitreous, respectively defined by texture and colour. Ochreous goethite is friable and yellow whereas vitreous goethite is hard, glassy and brown. These two subtypes have different processing and metallurgical behaviour and their discrimination is a challenge for the iron ore mining industry. The main goal of this paper is to offer characterisation techniques that provide objective means of discriminating the two subtypes even when they occur together.

Also

Feroxyhyte is an oxide/hydroxide of iron, δ-Fe3+O(OH). Feroxyhyte crystallizes in the hexagonal system. It forms as brown rounded to concretionary masses.

Forms under high pressure conditions and reverts to goethite on exposure to surface conditions.

(This page says it's stable? It's mined in vast quantities in Western Australia, but as geothite)

MinDat says

Polymorph of Geothite : Feroxyhyte, Lepidocrocite, UM1985-08-OH:Fe The most common simple iron oxide mineral. A weathering product of numerous iron-bearing minerals.

Goethite may crystallize from a precursor - a not approved species called 'proto-goethite'. May also form due to mineralization of lichen (Parmelia conspersa) thalli on metamorphics (e.g., gneisses), granites, feldspars.

Sulfidation of goethite into mackinawite and pyrrhotite is described by Wang et al. (2015); the process is inactive in the CH4 atmosphere but is triggered by the addition of CO2.

Couldn't it just be described as yellow ochre or black and glassy?

Signed - Nick Chopper, Wamego, KS 49.183.158.187 (talk) 03:53, 13 May 2022 (UTC)[reply]