Dickinsonite Value, Price, and Jewelry Information

Dickinsonite

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 Information

Data Value
Name Dickinsonite
Colors Oil green, olive green, yellowish green, brownish green, brownish.
Hardness 3.5 - 4
Fracture Uneven
Cleavage Perfect and easy, 1 direction
Stone Sizes Very tiny green gems, less than 1-2 carats, have been cut from Connecticut material.
Formula H2Na6(Mn,Fe,Ca,Mg)14(PO4)12 · H2O.
Crystallography Monoclinic. Crystals tabular, pseudorhombohedral; foliated, micaceous, radiating.
Refractive Index 1.648-1.671
Birefringence 0.013-0.014
Dispersion Strong
Luminescence None observed.
Luminescence Present No
Absorption Spectrum Not diagnostic.
Pleochroism Pale olive green to pale yellowish green.
Optics = 1.648-1.658; β = 1.655-1.662; γ = 1.662-1.671. Biaxial (+), 2V ~90°.
Optic Sign Biaxial +
Luster Vitreous; pearly on cleavage.
Specific Gravity 3.38-3.41
Transparency Transparent to translucent.

 

Optics= 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.