Related Research Articles
Nepheline syenite is a holocrystalline plutonic rock that consists largely of nepheline and alkali feldspar. The rocks are mostly pale colored, grey or pink, and in general appearance they are not unlike granites, but dark green varieties are also known. Phonolite is the fine-grained extrusive equivalent.
Eudialyte, whose name derives from the Greek phrase Εὖ διάλυτος, eu dialytos, meaning "well decomposable", is a somewhat rare, nine member ring cyclosilicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites. Its name alludes to its ready solubility in acid.
Chondrodite is a nesosilicate mineral with formula (Mg,Fe)
5(SiO
4)
2(F,OH,O)
2. Although it is a fairly rare mineral, it is the most frequently encountered member of the humite group of minerals. It is formed in hydrothermal deposits from locally metamorphosed dolomite. It is also found associated with skarn and serpentinite. It was discovered in 1817 at Pargas in Finland, and named from the Greek for "granule", which is a common habit for this mineral.
Normandite is a brittle orange brown sorosilicate mineral discovered in 1997 by Charles Normand, of Montreal. Normandite occurs in Khibiny Massif, Kola, Russia; in Poudrette quarry, Mont-Saint-Hilaire, Quebec and Tenerife, Canary Islands. It is found in nepheline syenite and in miarolitic cavities in nepheline syenite, associated with nepheline, albite, microcline, aegirine, natrolite, catapleiite, kupletskite, eudialyte, cancrinite, villiaumite, rinkite, and donnayite-(Y).
Lorenzenite is a rare sodium titanium silicate mineral with the formula Na2Ti2Si2O9 It is an orthorhombic mineral, variously found as colorless, grey, pinkish, or brown crystals.
Perovskite (pronunciation: ) is a calcium titanium oxide mineral composed of calcium titanate (chemical formula CaTiO3). Its name is also applied to the class of compounds which have the same type of crystal structure as CaTiO3 (XIIA2+VIB4+X2−3), known as the perovskite structure. Many different cations can be embedded in this structure, allowing the development of diverse engineered materials.
Alluaivite is a rare mineral of the eudialyte group, with complex formula written as Na19(Ca,Mn)6(Ti,Nb)3Si26O74Cl·2H2O. It is unique among the eudialyte group as the only titanosilicate (other representatives of the group are usually zirconosilicates). The two dual-nature minerals of the group, being both titano- and zirconosilicates, are labyrinthite and dualite. They both contain alluaivite module in their structures. Alluaivite is named after Mt. Alluaiv in Lovozero Tundry massif, Kola Peninsula, Russia, where it is found in ultra-agpaitic, hyperalkaline pegmatites.
Banalsite is a rare barium, sodium aluminium silicate mineral with formula: BaNa2Al4Si4O16. Banalsite is a tectosilicate of the feldspar group.
Vlasovite is a rare inosilicate (chain silicate) mineral with sodium and zirconium, with the chemical formula Na2ZrSi4O11. It was discovered in 1961 at Vavnbed Mountain in the Lovozero Massif, in the Northern Region of Russia. The researchers who first identified it, R P Tikhonenkova and M E Kazakova, named it for Kuzma Aleksevich Vlasov (1905–1964), a Russian mineralogist and geochemist who studied the Lovozero massif, and who was the founder of the Institute of Mineralogy, Geochemistry, and Crystal Chemistry of Rare Elements, Moscow, Russia.
Tuperssuatsiaite is a rare clay mineral found in Greenland, Namibia and Brazil. It is a hydrated phyllosilicate of sodium and iron.
Donnayite-(Y) is a rare-earth carbonate mineral containing the rare-earth metal yttrium. It was first discovered in 1978 at Mont Saint-Hilaire, Quebec. Donnayite was subsequently identified and named after Joseph D. H. Donnay and his wife, Gabrielle Donnay. Both were prominent mineralogists and crystallographers, and J. D. H. Donnay was awarded the Roebling Award by the Mineralogical Society of America in 1971 for his emphasis on the importance of optical mineralogy and crystal morphology. Donnayite tends to occur in small quantities in the pegmatite dykes and miarolitic cavities of mountainous regions. It crystallizes in this environment with increasing alkalinity values until the alkalinity suddenly drops during the last stage of crystallization. This results in increasing amounts of Na carbonates and REE minerals. First discovered at Mont St-Hilaire, donnayite has since been found in the Southern Ural Mountains of Russia and the Narssarssuk pegmatite of South Greenland. Donnayite crystals tend to be small and the color is commonly pale yellow to yellow with a white streak and a vitreous luster. Donnayite crystals usually display trigonal or hexagonal symmetry and have a hardness of 3. Twinning is extremely common in this mineral. Minerals closely related to donnayite include synchysite, calcite, sphalerite, microcline, and analcime. Donnayite is isomorphous with weloganite and mckelveyite.
Serandite is a mineral with formula Na(Mn2+,Ca)2Si3O8(OH). The mineral was discovered in Guinea in 1931 and named for J. M. Sérand. Serandite is generally red, brown, black or colorless. The correct name lacks an accent.
Dualite is a very rare and complex mineral of the eudialyte group, its complexity being expressed in its formula Na
30(Ca,Na,Ce,Sr)
12(Na,Mn,Fe,Ti)
6Zr
3Ti
3MnSi
51O
144(OH,H
2O,Cl)
9. The formula is simplified as it does not show the presence of cyclic silicate groups. The name of the mineral comes from its dual nature: zircono- and titanosilicate at once. Dualite has two modules in its structure: alluaivite one and eudialyte one. After alluaivite and labyrinthite it stands for third representative of the eudialyte group with essential titanium.
Labyrinthite is a very rare mineral of the eudialyte group. When compared to other species in the group, its structure is extremely complex - with over 100 sites and about 800 cations and anions - hence its name, with its complexity expressed in its chemical formula (Na,K,Sr)35Ca12Fe3Zr6TiSi51O144(O,OH,H2O)9Cl3. The formula is simplified as it does not show the presence of cyclic silicate groups. Complexity of the structure results in symmetry lowering from the typical centrosymmetrical group to R3 space group. Other eudialyte-group representatives with such symmetry lowering include aqualite, oneillite, raslakite, voronkovite. Labyrinthite is the second dual-nature representative of the group after dualite and third with essential titanium after dualite and alluaivite.
Ferrokentbrooksite is a moderately rare mineral of the eudialyte group, with formula Na15Ca6(Fe,Mn)3Zr3NbSi25O73(O,OH,H2O)3(Cl,F,OH)2. The original formula was extended form to show the presence of cyclic silicate groups and presence of silicon at the M4 site, according to the nomenclature of eudialyte group. As suggested by its name, it is the (ferrous) iron analogue of kentbrooksite. When compared to the latter, it is also chlorine-dominant instead of being fluorine-dominant. The original (holotype) material is also relatively enriched in rare earth elements, including cerium and yttrium.
Taseqite is a rare mineral of the eudialyte group, with chemical formula Na12Sr3Ca6Fe3Zr3NbSiO(Si9O27)2(Si3O9)2(O,OH,H2O)3Cl2. The formula given is derived from the original one and shows a separate silicon at the M4 site, basing on the nomenclature of the eudialyte group. Taseqite, khomyakovite and manganokhomyakovite are three group representatives with species-defining strontium, although many other members display strontium diadochy. Both strontium (N4Sr) and niobium (M3Nb) are essential in the crystal structure of taseqite. When compared to khomyakovite, taseqite differs in niobium- and chlorine-dominance.
Kentbrooksite is a moderately rare mineral of the eudialyte group, with chemical formula (Na,REE)15(Ca,REE)6Mn3Zr3NbSi[(Si9O27)2(Si3O9)2O2]F2·2H2O. This extended formula shows the presence of cyclic silicate groups and dominance of Si at the M4 site, according to the nomenclature of the eudialyte group. The characteristic features of kentbrooksite, that make it different from eudialyte are: (1) dominancy of fluorine (the only currently known example among the whole group), (2) dominancy of manganese, and (3) dominancy of niobium. Trace hafnium and magnesium are also reported. Kentbrooksite is relatively common when compared to most other species of the group.
Oneillite is a rare mineral of the eudialyte group with the chemical formula Na15Ca3Mn3Fe2+3Zr3NbSiO(Si3O9)2(Si9O27)2(O,OH,H2O)3(OH,Cl)2. The formula is based on the original one but extended to show the presence of cyclic silicate groups and domination of Si at the M4 site. The mineral has lowered symmetry (space group R3, instead of more specific for the group R3m one) due to Ca-Mn ordering. Similar feature is displayed by some other eudialyte-group members: aqualite, labyrinthite, raslakite, and voronkovite. Oneillite is strongly enriched in rare earth elements (REE, mainly cerium), but REE do not dominate any of its sites.
Voronkovite is a very rare mineral of the eudialyte group with the chemical formula Na15(Na,Ca,Ce)3(Mn,Ca)3Fe3Zr3Si2Si24O72(OH,O)4Cl·H2O. The formula is based on the simplified original one; it does not show the presence of cyclic silicate groups, but two M3- and M4-site silicon atoms are shown separately (basing on the nomenclature of the eudialyte group). Voronkovite has lowered symmetry (space group R3, instead of more specific for the group R3m one), similarly to some other eudialyte-group members: aqualite, labyrinthite, oneillite and raslakite. The specific feature of voronkovite is, among others, strong enrichment in sodium.
Rastsveatevite is a rare mineral of the eudialyte group with the chemical formula Na27K8Ca12Fe3Zr6Si4[Si3O9]4[Si9O27]4(O,OH,H2O)6Cl2. Its structure is modular. It is only the third member of the group after andrianovite and davinciite with essential (site-dominating) potassium. Potassium and sodium enter both N4 and M2 sites. The mineral is named after Russian crystallographer Ramiza K. Rastsvetaeva.
References
- ↑ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID 235729616.
- 1 2 3 Mindat.org
- ↑ Webmineral data
- ↑ Mineralien Atlas
- ↑ Jambor, J.L.; Roberts, A.C. (January 2004). "New Mineral Names" . American Mineralogist. 89 (1): 249–253.
- ↑ Christiansen, Claes C., Ole Johnsen and Emil Makovicky, Crystal Chemistry of the Rosenbuscite Group, The Canadian Mineralogist, Vol. 41, pp. 1203-1224 (2003)
- ↑ Mandarino, J.A. (2004) Abstracts of New Mineral Descriptions. The Mineralogy Record, 35, 354-355
- 1 2 3 Christiansen, C.C., Gault, R.A., Grice, and J.D., Johnsen, O. (2003) Kochite, a new member of the rosenbuschite group from the Werner Bjerge alkaline complex, East Greenland. European Journal of Mineralogy, 15, 551-554 ]