Weloganite | |
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General | |
Category | Carbonate mineral |
Formula (repeating unit) | Na 2(Sr,Ca)3 Zr(C O 3)6·3H2O |
IMA symbol | Wlg [1] |
Strunz classification | 5.CC.05 |
Dana classification | 15.3.4.4 |
Crystal system | Triclinic |
Crystal class | Pedial (1) (same H-M symbol) |
Space group | P1 |
Unit cell | a = 8.966 Å, b = 8.98 Å c = 6.73 Å; α = 102.72° β = 116.65°, γ = 60.06°; Z = 1 |
Identification | |
Formula mass | 814.16 g/mol |
Color | Yellow, pale yellow, amber, tan, white |
Crystal habit | Roughly hexagonal, tapering crystals, pseudorhombohedral |
Twinning | About [103] repeated at 120 degrees |
Cleavage | Perfect on pseudo {0001} |
Fracture | Conchoidal |
Mohs scale hardness | 3+1⁄2 |
Luster | Vitreous |
Streak | White |
Diaphaneity | translucent |
Specific gravity | 3.20–3.22 |
Optical properties | Biaxial (−) |
Refractive index | nα = 1.558 nβ = 1.646 nγ = 1.640 |
Birefringence | δ = 0.082 |
2V angle | Measured: 15° |
Dispersion | Weak |
Other characteristics | Pyroelectric. triboluminescent. |
References | [2] [3] [4] [5] [6] |
Weloganite is a rare carbonate mineral with the formula: Na 2(Sr,Ca)3 Zr(C O 3)6·3H2O. It was discovered by Canadian government mineralogist Ann P. Sabina in 1967 and named for Canadian geologist Sir William Edmond Logan (1798–1875). It was first discovered in Francon Quarry, [7] Montreal, Quebec, Canada and has only been reported from a few localities worldwide.
It is usually white, lemon yellow, or amber in color, and can be translucent. It crystallizes in the triclinic system and shows pseudo-hexagonal crystal forms due to twinning. The width of the crystals typically undulates down the length, forming crystals that widen in the middle or flare out at the end. Crystals are affected by light and can develop a white alteration coating over time. Weloganite is triboluminescent, producing blue light.
The mineral occurs in an igneous carbonatite sill in Montreal, Quebec, Canada in the Francon Quarry where it was first discovered. It also occurs in the Mont Saint-Hilaire district. Associated minerals include strontianite, dawsonite and calcite. It has also been reported from the Pilansberg Complex of the western Bushveld Igneous Complex in South Africa. [5]
Strontianite (SrCO3) is an important raw material for the extraction of strontium. It is a rare carbonate mineral and one of only a few strontium minerals. It is a member of the aragonite group.
Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula Na2Al2Si3O10·2H2O. The type locality is Hohentwiel, Hegau, Germany.
Gmelinite-Na is one of the rarer zeolites but the most common member of the gmelinite series, gmelinite-Ca, gmelinite-K and gmelinite-Na. It is closely related to the very similar mineral chabazite. Gmelinite was named as a single species in 1825 after Christian Gottlob Gmelin (1792–1860) professor of chemistry and mineralogist from Tübingen, Germany, and in 1997 it was raised to the status of a series.
Gmelinite-Na has been synthesised from Na-bearing aluminosilicate gels. The naturally occurring mineral forms striking crystals, shallow, six sided double pyramids, which can be colorless, white, pale yellow, greenish, orange, pink, and red. They have been compared to an angular flying saucer.
Sperrylite is a platinum arsenide mineral with the chemical formula PtAs2 and is an opaque metallic tin white mineral which crystallizes in the isometric system with the pyrite group structure. It forms cubic, octahedral or pyritohedral crystals in addition to massive and reniform habits. It has a Mohs hardness of 6–7 and a very high specific gravity of 10.6.
Geigerite is a mineral, a complex hydrous manganese arsenate with formula: Mn5(AsO3OH)2(AsO4)2·10H2O. It forms triclinic pinacoidal, vitreous, colorless to red to brown crystals. It has a Mohs hardness of 3 and a specific gravity of 3.05.
Sabinaite (Na4Zr2TiO4(CO3)4) is a rare carbonate mineral. It crystallizes in the monoclinic crystal system as colorless to white prisms within cavities. It is more typically found as powdery coatings and masses. It has a specific gravity of 3.36.
Howlite, a calcium borosilicate hydroxide (Ca2B5SiO9(OH)5), is a borate mineral found in evaporite deposits.
Braggite is a sulfide mineral of platinum, palladium and nickel with chemical formula: S. It is a dense, steel grey, opaque mineral which crystallizes in the tetragonal crystal system. It is the central member in the platinum group end-members cooperite and vysotskite.
Leightonite is a rare sulfate mineral with formula of K2Ca2Cu(SO4)4•2H2O.
Kochite is a rare silicate mineral with chemical formula of (Na,Ca)3Ca2(Mn,Ca)ZrTi[(F,O)4(Si2O7)2] or double that. Kochite is a member of the rosenbuschite group.
Gabrielite is an extremely rare thallium sulfosalt mineral with a chemical formula of Tl6Ag3Cu6(As,Sb)9S21 or Tl2AgCu2As3S7.
Quintinite is a carbonate mineral with the chemical formula Mg4Al2(OH)12CO3⋅3H2O.
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.
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.
Huemulite is a mineral with formula Na4Mg(V10O28)·24H2O that is yellow to orange in color. It was first discovered in Argentina in 1959 and described in 1966. The mineral is named for the Huemul mine in which it was discovered.
Ann Phyllis Sabina Stenson was a Canadian mineralogist, gemmologist, teacher, public servant and popular science author. Sabina has been instrumental in the development of X-ray diffraction as a means of identifying minerals. She is credited with the discovery of a variety of different minerals and currently has one named in her honor: Sabinaite. a string of educational books and guides that focus on the study of numerous minerals throughout Canada, and has been important in the creation of a number of geological associations.
John Leslie Jambor was a Canadian geologist and mineralogist. Jambor was an exceptional figure in the field of mineralogy and a major contributor to the Mineralogical Association of Canada (MAC).
Jambor has a Scopus h-index of 38.
Dresserite is a mineral of the dresserite group, named in honor of John Alexander Dresser, geologist. It was approved by the IMA in 1968, but only a year after was it published. The rare mineral can only be found in Francon quarry, Canada. The quarry is located in the middle of the city of Montréal, but had been closed in 1981 and will not reopen in the future.
Lizardite is a mineral from the serpentine subgroup with formula Mg3(Si2O5)(OH)4, and the most common type of mineral in the subgroup. It is also a member of the kaolinite-serpentine group.
Doyleite is a rare aluminum trihydroxide mineral named in honor of its discoverer, the Canadian physician Earl Joseph (Jess) Doyle. It was first definitively described in 1985 and it is approved by the IMA. It was described from Mont Saint-Hilaire, where it is extremely rare.