Malacon is a mineraloid, a type of zircon (Naegite) Zr [SiO 4 ], with a high content of thorium and rare earth elements. It is found mainly in subalkaline granitoids , albitites, pegmatites , hydrothermal deposits of thorium.
| Malacon | |
|---|---|
 Brazil Malacon Sample | |
| Formula | Zr [SiO 4 ] |
| Impurity | thorium, rare earths |
| Opening year | 1844 |
| Physical properties | |
| Colour | yellowish to dark brown [1] , often spotty or zonal |
| Trait color | missing |
| Shine | glass |
| Hardness | 7 |
| Cleavage | missing |
| Kink | conchoid |
| Syngonia | tetragonal |
First described by in 1844 [2] .
It is characterized by complete or partial metamyctality [1] , the presence of adsorbed water; hardness (7 on the Mohs scale) is reduced in comparison with crystalline zircon (7.5), which is the reason for the name (from the Greek. malakos - “soft”). The density and content of ZrO 2 is also lower than that of zircon.
Habitus from short-prismatic to bipyramidal; has characteristic radially radiant discharge and intergrowths. Coloring from yellowish to dark brown, often spotty or zonal.
It is practically not used as zirconium ore, but can serve as a source of rare earth elements , in particular, scandium . Due to the content of thorium, it has radioactivity and is used to determine the absolute age of rocks by the uranium-lead method .
Other properties
- glitter glass
- kinky conch
- cleavage is missing
- average weight
- trait is missing
- tetragonal syngony
- igneous genesis.
Notes
- ↑ 1 2 Shtrubel G., 1987 .
- ↑ Th. Scheerer. Polykras und Malakon, zwei neue Mineralspecies (German) // Annalen der Physik und Chemie. - Herausgegeben zu Berlin von JC Poggendorff, 1844. - Bd. 138 , H. 7 . - S. 429-443 . - ISSN 0003-3804 . - DOI : 10.1002 / andp.18441380715 .
Bibliography
- Lacroix, A. Malacon // Minéralogie de Madagascar: [ fr. ] / Éd. A. Challamel. - Paris: Librairie Maritime et Coloniale, 1922. - T. 1. - P. 239−242.
- Shtrubel, G. Malakon // Mineralogical Dictionary / G. Shtrubel, Z. H. Zimmer; per. with him. E.V. Pryakhina, N. B. Zdorik; under the editorship of D.A. Mineeva, T. B. Zdorik. - M .: Nedra, 1987 .-- S. 255−256.
- Feldman, L.G. Malakon // Mountain Encyclopedia / ed. E. A. Kozlovsky. - M .: Soviet Encyclopedia, 1987. - T. 3. - S. 247.