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Neotocite
Current inventory:  0 gems
 

  
Neotocite is named from the Greek word neotokos, meaning of recent origin, as it is an alteration product of other minerals.

Discovered in 1848;   IMA status: Valid (pre-IMA; Grandfathered)

Chemistry

Chemical Formula:

(Mn²⁺Fe²⁺)SiO₃ · H₂O(?)

Hydrated Manganese Iron Silicate

Molecular Weight:

149.26 gm

Composition: 

Classification

Mineral Classification:

Silicates (Germanates)

Strunz 8th Ed. ID:

8/H.21-60

Nickel-Strunz 10th Ed. ID:

9.ED.20

9 : SILICATES (Germanates)
E : Phyllosilicates
D : Phyllosilicates with kaolinite layers composed of tetrahedral and octahedral nets

Related to:

Allophane Group

Synonyms:

Neotokite, Chinglusuite, Penwithite, Stratospeite, Sturtite, Vittinkite, Wittingite

Crystal Data

Crystallography:

Amorphous

Crystal Habit:

No crystals since it is Amorphous

Twinning:

None

Physical Properties

Cleavage:

None

Fracture:

Conchoidal

Tenacity:

Brittle

Moh's Hardness:

3.0 - 4.0

Density:

2.1 - 2.7 (g/cm³)

Luminescence:

None

Radioactivity:

Not Radioactive

Optical Properties

Color:

Black, dark Brown, liver Brown, Olive Green

Transparency:

Opaque, Translucent in thin fragments

Luster:

Dull to Resinous or Vitreous, may be slightly metallic

Refractive Index:

1.50 - 1.65  Isotropic

Birefringence:

0.00 (Isotropic)

Occurances

Geological Setting:

An alteration product of manganese-bearing silicate minerals.

Common Associations:

Calcite, Quartz, Rhodonite

Common Impurities:

Al, Mg, Ca, Na, K, C

Type Locality:

Erik Ers Mine, Torsåker, Hofors, Gästrikland, Sweden

Year Discovered:

1848

View mineral photos:

Neotocite Mineral Photos and Locations

More Information

Mindat.org
Webmineral.com

Neotocite, also known as Penwithite, is similar in composition to Serpentine and is an alteration product of Bementite. It is not a scarce mineral but rarely available as a faceted gem. Neotocite is always opaque and usually a shade of liver brown.

Neotocite is found in many locations worldwide including Mitterdorf, Styria, Austria; Mont Saint-Hilaire, Rouville County, Québec, Canada; Valgraveglia Mine, Reppia, Graveglia Valley, Ne, Genova Province, Liguria, Italy; Noda-Tamagawa mine, Iwate Prefecture, Tohoku Region, Honshu Island, Japan; Lovozero Massif, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia; Harstigen Mine, Pajsberg, Filipstad, Värmland, Sweden; and Franklin, Franklin Mining District, Sussex County, New Jersey, USA.
 

  
Neotocite gems for sale:

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