Dickinsonite Value, Price, and Jewelry Information


This mineral is seldom even mentioned in the gem literature because it is so rare and has been so seldom cut. Faceted gems are practically nonexistent, and would be among the rarest of all cut stones.

Dickinsonite Value

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Dickinsonite Information

DataValue
NameDickinsonite
Crystallography Monoclinic. Crystals tabular, pseudorhombohedral; foliated, micaceous, radiating.
Colors Oil green, olive green, yellowish green, brownish green, brownish.
Luster Vitreous; pearly on cleavage.
Fracture Uneven.
Hardness 3.5-4
Specific Gravity 3.38-3.41
Birefringence 0.013-0.014
Cleavage Perfect and easy, 1 direction.
Dispersion Strong
Stone SizesVery tiny green gems, less than 1-2 carats, have been cut from Connecticut material.
Luminescence None observed
Spectral Not diagnostic.
FormulaH2Na6(Mn,Fe,Ca,Mg)14(PO4)12 · H2O.
Pleochroism Pale olive green to pale yellowish green.

 

Opticsa= 1.648-1.658; β = 1.655-1.662; γ=1.662-1.671.

Biaxial (+), 2V ~90°.

Occurrence: A secondary phosphate mineral in granite pegmatites.

Branchville, Connecticut; Portland, Connecticut; Poland, Maine.

Comments: This mineral is seldom even mentioned in the gem literature because it is so rare and has been so seldom cut. Faceted gems are practically nonexistent, and would be among the rarest of all cut stones.

Name: After the Rev. William Dickinson in recognition of his interest in the locality where first found.