Mineralpedia Details for Serandite

More properly spelled Sérandite, this mineral is named for West African mineral collector J.M Sérand who also assisted in the collection of the type material from Rouma Island of Guinea. Occurs in several environments including in sodalite xenoliths and pegmatites that cut syenite and nepheline syenites in pegmatite, in phonolite vugs, and in volcanogenic manganese deposits affected by contact metamorphism.

Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/serandite.pdf

Formula

NaMn²⁺₂Si₃O₈(OH) 

Crystal System

Triclinic 

Crystal Habit

Prismatic 

Cleavage

Perfect, Perfect, None 

Luster

Vitreous - Pearly 

Color

light brown, light pink, orange red 

Streak

white 

Class

Triclinic - Pinacoidal 

Hardness

4.5-5.5 

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Salmon pink crystals the largest is a tabular crystal to 1cm.

Pink cluster of Serandite crystals, mostly in parallel growth. The crystals on the front are to about 1.5cm. All the crystals are cavernous - are hollow. Serandite is the Mn end member of Pectolite. The white mineral is Albite.

Very nice long thin blade of salmon-pink Serandite with smaller bladed Serandite crystals to 1.5cm and red-orange stubby prismatic Mangan-neptunite crystals to 2mm. Overall 11.5 x 0.7 x 3cm.

Salmon colored thick tabular crystal, doubly terminated to 5.5cm associated with long prismatic Aegerine to 4.5cm.

7mm Serandite crystal on Sodalite replaced by Catapleiite.

Light pink prismatic crystal to 2.5cm in purple Ussingite matrix.

Reddish long bladed crystals to over 3cm in Ussingite matrix.

Orange brown bladed crystals to 1.5cm in purple Ussingite matrix with white, platy Vuonnemite.

Lovozero is a big area and this specimen deserves a more specific locality. But if I had to guess it would be from the Shkatulka pegmatite of the Umbozero mine. It is by Igor Pekov's study the largest Ussingite body in the world and occcupies the core of this pegmatite. It is a remarkable 12 x 3 meters in size! Serandite occured in the outer fringes of the Ussingite core at Shkatulka in crystals up to 30cm long. Igor Pekov's book on Lovozero Massif is an informative resource on the subject.

This specimen has carrot to orange brown bladed crystals to 3cm with large plates of Vuonnemite to 3cm. Minerals in this pegmatite are considered hyperalkaline (extremely alkaline).

Salmon pink bladed crystals to 3.5cm with white, radial Leifite and white Analcime.

Pink bladed Serandite to 3cm in pink Ussingite matrix with with Mountainite. 

Pink salmon colored Serandite elongated crystals packed tightly with Ussingite (lilac), Steenstrupine (dark brown, metamict) and Bornemanite (creamy yellow). Ex. Dr. J. Hyrsl.