Normandite is a brittle orange brown sorosilicate

Silicate minerals

The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group...

 mineral discovered in 1997 by Charles Normand (1963-), of Montreal. Normandite occurs in Khibiny Massif

Khibiny Massif

The Khibiny Massif, Khibiny Mountains, Khibinsky Mountains or Khibins, Khibinsky tundras, Khibiny is one of the two main mountain ranges of the Kola Peninsula, Russia, within the Arctic Circle, located between Imandra and Umbozero lakes.The massif is of oval shape of about 1,300 sq.km...

, Kola

Kola

Kola can refer to:*Kola nut, a genus of about 125 species of trees**Inca Kola, a cola soft drink made in Peru**Kola Real, a Peruvian soft drink**Kola Inglesa , a Peruvian soft drink...

, Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

; in Poudrette quarry, Mont-Saint-Hilaire, Quebec

Mont-Saint-Hilaire, Quebec

Mont-Saint-Hilaire is an off-island suburb of Montréal in southeastern Québec, Canada on the Richelieu River in the Regional County Municipality of La Vallée-du-Richelieu...

 and Tenerife

Tenerife

Tenerife is the largest and most populous island of the seven Canary Islands, it is also the most populated island of Spain, with a land area of 2,034.38 km² and 906,854 inhabitants, 43% of the total population of the Canary Islands. About five million tourists visit Tenerife each year, the...

, Canary Islands

Canary Islands

The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...

. It is found in nepheline syenite

Nepheline syenite

Nephelene 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...

 and in miarolitic cavities

Miarolitic cavities

Miarolitic cavities are typically crystal lined irregular cavities or vugs most commonly found in granitic pegmatites, but also found in a variety of igneous rocks. The central portions of pegmatites are often miarolitic as the pegmatite dike crystallizes from the outside walls toward the center...

 in nepheline syenite, associated with nepheline

Nepheline

Nepheline, also called nephelite , is a feldspathoid: a silica-undersaturated aluminosilicate, Na3KAl4Si4O16, that occurs in intrusive and volcanic rocks with low silica, and in their associated pegmatites...

, albite

Albite

Albite is a plagioclase feldspar mineral. It is the sodium endmember of the plagioclase solid solution series. As such it represents a plagioclase with less than 10% anorthite content. The pure albite endmember has the formula NaAlSi3O8. It is a tectosilicate. Its color is usually pure white, hence...

, microcline

Microcline

Microcline is an important igneous rock-forming tectosilicate mineral. It is a potassium-rich alkali feldspar. Microcline typically contains minor amounts of sodium. It is common in granite and pegmatites. Microcline forms during slow cooling of orthoclase; it is more stable at lower temperatures...

, aegirine

Aegirine

Aegirine is a member of the clinopyroxene group of inosilicates. Aegirine is the sodium endmember of the aegirine-augite series. Aegirine has the chemical formula NaFeSi2O6 in which the iron is present as Fe3+. In the aegirine-augite series the sodium is variably replaced by calcium with iron and...

, natrolite

Natrolite

Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula . The type locality is Hohentwiel, Hegau, Germany....

, catapleiite, kupletskite, eudialyte

Eudialyte

Eudialyte, whose name derives from the Greek phrase Εὖ διάλυτος eu dialytos, meaning "well decomposable", is a somewhat rare, red silicate mineral, which forms in alkaline igneous rocks, such as nepheline syenites...

, cancrinite

Cancrinite

Cancrinite is a complex carbonate and silicate of sodium, calcium and aluminium with the formula Na6Ca2[2|Al6Si6O24]·2H2O. It is classed as a member of the feldspathoid group of minerals; the alkali feldspars that are poor in silica. Yellow, orange, pink, white or even blue, it has a vitreous or...

, villiaumite

Villiaumite

Villiaumite is a rare halide mineral composed of sodium fluoride, NaF. It is very soluble in water and some specimens fluoresce under long and short wave ultraviolet light. It has a Mohs hardness of 2.5 and is usually red, pink, or orange in color...

, rinkite, and donnayite-(Y).

Normandite has a chemical formula of NaCa(Mn²⁺,Fe²⁺)(Ti,Nb,Zr)Si₂O₇(O,F)₂. It crystallizes in the monoclinic-prismatic crystal system. It occurs as transparent to translucent orange-brown aggregates of subparallel acicular

Crystal habit

Crystal habit is an overall description of the visible external shape of a mineral. This description can apply to an individual crystal or an assembly of crystals or aggregates....

 crystals up to 10 mm in length, and as patches of yellow, fibrous crystals. It has a white to very pale yellow streak and vitreous luster. It is brittle, with distinct {100} and {001} cleavages, and a conchoidal fracture. It has a specific gravity

Specific gravity

Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...

 of 3.48 to 3.5, a Mohs hardness of 5 to 6 and refractive index

Refractive index

In optics the refractive index or index of refraction of a substance or medium is a measure of the speed of light in that medium. It is expressed as a ratio of the speed of light in vacuum relative to that in the considered medium....

values of nα=1.743, nβ=1.785 and nγ=1.810.