dioptase (w. duftite and malachite)

TSNB417

Specimen

Exhibit 1. Dioptase (w. duftite and malachite); 45 mm.
Exhibit 1. Dioptase (w. duftite and malachite); 45 mm.
Image Credit: Malcolm Southwood
Exhibit 2. Analytical data; duftite. (M. Southwood and P. Carr; unpublished).
Exhibit 2. Analytical data; duftite. (M. Southwood and P. Carr; unpublished).
Image Credit: Malcolm Southwood
Exhibit 3. Analytical data. Duftite on this specimen (blue circles) is calcium rich.
Exhibit 3. Analytical data. Duftite on this specimen (blue circles) is calcium rich.
Image Credit: Malcolm Southwood
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Title

dioptase (w. duftite and malachite)

Principal Mineral

Dioptase

Size

Miniature; 45mm

Location in the Mine

Second oxidation zone

Collection

Southwood, M. MS2017.041

Provenance

Sussman, M.; Veevaert, J.

Entry Type

Specimen TSNB417

Description

A siliceous matrix hosting a shallow vug containing well-formed iron-stained quartz crystals (to 8 mm) with a patchy coating of apple-green duftite microcrystals, and several prominent crystals of bluish-green dioptase (to 7mm) with a slightly etched appearance. Sprays of primary malachite overgrow all of the other minerals, so that the crystallisation sequence appears to be quartz >> duftite >> dioptase >> malachite. There is no sign of either calcite or dolomite on this specimen. WDS analysis confirms that the arsenate is a Ca-rich duftite (exhibits 2 and 3). 

The specimen was purchased in 2007 from John Veevaert, accompanied by an older Marshall Sussman (Crystal Cellar) label.

Associated Minerals

duftite; malachite; quartz