Potassic-mangani-leakeite

Bernard Elgey Leake

Formula:

[(Na,K)][Na₂][Mg₂Mn³⁺₂Li]Si₈O₂₂(OH)₂

The Leakeite group minerals are sodium amphiboles defined with:
^A(Na+K+2Ca)> 0.5 apfu,
^C(Al+Fe³⁺+2Ti) > 1.5 apfu and
^CLi > 0.5 apfu

Potassic-mangani-leakeite is defined with
A position: Na dominant
C²⁺ position: Mg dominant
C³⁺ position: Mn dominant
W position: (OH) dominant

Colour:

Dark red to brownish-lilac.

Lustre:

Vitreous

Hardness:

6 - 7

Crystal System:

Monoclinic

Member of:

Leakeite Root Name Group > Sodium Amphibole Subgroup > w(OH, F, Cl)-dominant Amphibole Group > Amphibole Supergroup

Name:

This mineral was originially named kornite for Hermann Korn (b. 1946), German geologist. Kornite was discredited in the 2012 amphibole nomenclature and the mineral renamed potassic-mangani-leakeite.

Type Locality:

ⓘ Wessels Mine, Hotazel, Kalahari manganese field, Northern Cape, South Africa

Classification of Potassic-mangani-leakeiteHide

Physical Properties of Potassic-mangani-leakeiteHide

Optical Data of Potassic-mangani-leakeiteHide

Type:

Biaxial (-)

RI values:

n_α = 1.654 n_β = 1.675 n_γ = 1.696

2V:

Measured: 88° to 92°, Calculated: 88°

Max Birefringence:

δ = 0.042

Image shows birefringence interference colour range (at 30µm thickness)
and does not take into account mineral colouration.

Surface Relief:

High

Dispersion:

r < v distinct

Chemical Properties of Potassic-mangani-leakeiteHide

Crystallography of Potassic-mangani-leakeiteHide

Type Occurrence of Potassic-mangani-leakeiteHide

Synonyms of Potassic-mangani-leakeiteHide

Other Language Names for Potassic-mangani-leakeiteHide

Relationship of Potassic-mangani-leakeite to other SpeciesHide

Related Minerals - Nickel-Strunz GroupingHide

Related Minerals - Dana Grouping (8th Ed.)Hide

Other InformationHide

References for Potassic-mangani-leakeiteHide

Internet Links for Potassic-mangani-leakeiteHide

Localities for Potassic-mangani-leakeiteHide

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.

Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (eg from pseudomorphs.)

All localities listed without proper references should be considered as questionable.

India
Madhya Pradesh Jhabua District ⓘ Kajlidongri Mine	Am Min 90:2-3 pp304-309
South Africa (TL)
Northern Cape Kalahari manganese field Hotazel ⓘ Wessels Mine (TL)	Schweiz.Min.Petr.Mitt.(1993) 73, 349-355; Gnos, E., Armbruster, T., & Villa, I. M. (2003). Norrishite, K (Mn23+ Li) Si4O10 (O) 2, an oxymica associated with sugilite from the Wessels Mine, South Africa: Crystal chemistry and 40Ar-39Ar dating. American Mineralogist, 88(1), 189-194.