Getite is a mineral named after the great German poet, philosopher, natural scientist and collector of minerals I.V. Goethe . A synonym is iron ore needle. a-FeOOH.
| Goethite | |
|---|---|
 Goethite from Brazil | |
| Formula | FeO (OH) |
| Physical properties | |
| Color | Shades of brown, yellow |
| Trait color | Tan |
| Shine | Diamond |
| Transparency | Translucent, opaque |
| Hardness | 5-5.5 |
| Cleavage | Perfect on {010} |
| Density | 3.3-4.3 g / cm³ |
| Syngonia | Rhombic (planaxial) |
Content
- 1 Properties
- 2 Forms of finding
- 3 Associated Minerals
- 4 Origin and deposits
- 5 Links
- 6 External links
Properties
Color : yellow, ocher-yellow, yellow-brown, brown. Shine : from diamond to dull, in fibrous differences - satin, silky. Translucent. Trait color (powder color) - from ocher yellow to brown yellow. Hardness : 5-5.5. Fragile. Density 4.3. Cleavage perfect in (010), clear in (100). Syngonia is a rhombic, rhombo-dipyramidal type of symmetry .
Locations
The crystals are needle, lamellar, columnar; earthy, powdery masses; kidney-shaped radial radiant fine-fiber aggregates (“brown glass head”); nostril nodules , spherulitic [1] kidney-shaped crusts and pseudostalactites [2] . Under the soldering tube it melts with difficulty, blackens and magnetizes (because it loses water and turns into magnetic oxide ). Soluble in hydrochloric acid .
Associated Minerals
Hematite , pyrite , siderite , lepidocrocite , jarosite , psilomelan , magnetite , quartz , chalcedony , calcite .
Origin and deposits
It occurs as a weathering product; formed at normal temperature and pressure from other iron-containing minerals: siderite, magnetite, pyrite, etc., or as a precipitation product in swamps and other natural sources. The main component of limonite is part of brown iron ore . Occasionally found as a hydrothermal mineral in the form of needle and columnar crystals. Often found in the form of inclusions in quartz crystals, in chalcedony and in agate .
It is very widespread. Examples of deposits: Pribram ( Czech Republic ); Broken Hill ( New South Wales , Australia ), Nob Lake ( Canada ), Lorraine ( France ); Cornwall County ( UK ); the pegmatite field Volodarsk-Volynskoe ( Ukraine ), the Middle and Southern Urals (Bakalskoe deposit, Gayskoye deposit, etc.), Kursk magnetic anomaly , etc.
Links
- ↑ Spherulites. - a note on the information server of the Geological Faculty of Moscow State University.
- ↑ Pseudostalactitis. - a note on the information server of the Geological Faculty of Moscow State University.