Marialite
- Mizzonit of pianura
Marialite is a rarely occurring mineral from the mineral class of " silicates and Germanates ". It crystallizes in the tetragonal crystal system with the composition Na 4 [Cl | Al3Si9O24 ], and is therefore chemically seen a sodium Gerüstalumosilikat with chlorine as an additional anion.
Marialite most developed prismatic crystals with flat, pyramidal ends with glass glossy surfaces, but also columnar or granular to massive mineral aggregates. In pure form, the mineral is colorless and transparent. Through multiple refraction due to lattice defects or multicrystalline training however, it may also appear white and gray, accept by foreign admixtures pink to violet, blue, yellow, brown or orange-brown color. However, his stroke color is always white.
Special Features
Under UV light, show some Marialithe orange to pale yellow or red fluorescence.
Etymology and history
Marialite was first discovered in pianura in the Phlegraean Fields in the Italian province of Naples.
Originally the name of Marialite Ryllo had been awarded for a white Berzellin of Albano. However, Gerhard vom Rath was able to show in 1866 that was identical to the Berzelin Haüyn already known. Berzelin as an independent mineral therefore had to be canceled and accordingly also lost the Varietätsbezeichnung Marialite their meaning.
Vom Rath hit the vacated Marialite name before as a name for a newly discovered mineral pianura in which he himself provisionally designated as Mizzonit of pianura due to its similarity to the Mizzonit.
Classification
In the now outdated but still in use 8th edition of the mineral classification by Strunz the Marialite belonged to the mineral class of " silicates and Germanates " and then to the Department of " framework silicates ( tectosilicates ) " where he alone together with Kalborsit, Mejonit, Sarkolith and Silvialith " scapolite series" with the system no. VIII/J.13 formed.
The 9th edition used since 2001 and valid by the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Marialite also in the class of " silicates and Germanates " there, however, in the newly defined division of the " framework silicates ( tectosilicates ) without zeolitic H2O " one. This department is also further divided according to the possible presence of other anions, so that the mineral is " with additional anions framework silicates ( tectosilicates )" area according to its composition in the subdivision of where it only together with Mejonit and Silvialith the " Skapolithgruppe " with the system number. 9.FB.15 forms.
The mainly common in English-speaking classification of minerals according to Dana assigns the Marialite in the class of " silicates and Germanates " and then in the Department of: a " framework silicates Al- Si lattice ". Here he is with Mejonit and Silvialith in the " Skapolithgruppe " with the system no. 76.03.01 within the subdivision: to find " 76.03 tectosilicates Al- Si lattice with other Be / Al / Si gratings ".
Education and Locations
Marialite forms in the formed by regional metamorphism rocks such as marble, calcareous gneisses, granulites and greenschist. He is also found in some skarns and pegmatites and in pneumatolytic or hydrothermally converted igneous rocks. Accompanying minerals include various plagioclase, garnets, pyroxenes, amphiboles, apatite and titanite and zircon.
A rare mineral formation Marialite has so far (as of 2011) are detected only at a few localities. Around 95 localities are known. Apart from its type locality pianura the mineral nor joined Soccavo in the Phlegraean Fields, at Ercolano and Santa Anastasia near the Monte Somma, Procida and Lavorate (Salerno) in Campania; in Val di Fà on the Valcamonica in Lombardy and in the " Cape Arco mine " in Porto Azzurro on Elba.
In Austria, found the mineral spodumene at a trial mining on fire back in Carinthia ( see also mining in Carinthia ).
Other localities lie including Australia, Brazil, Chile, China, France, Japan, Canada, Nepal, Norway, Russia, Sweden, Spain, South Africa, Tanzania, the Czech Republic, the United Kingdom ( UK) and the United States (USA).
Crystal structure
Marialite crystallized tetragonal space group I4 / m ( Raumgruppen-Nr. 87) with the lattice parameters a = 12.05 Å and c = 7.57 Å and two formula units per unit cell.