Editorial Feature

Balkanite – Occurrence, Properties, and Distribution

Jun 13 2014

Balkanite was named after the Balkan Mountains, where the mineral was first located.

Properties of Balkanite

The following are the key properties of balkanite:

Cell Data
- Space group: P222, Pmm2, or Pmmm
- a = 10.62(2)
- b = 9.42(2)
- c = 3.92(4)
- Z = 1

Crystal Data
- Orthorhombic
- Point group: 222, mm2, or 2/m 2/m 2/m
- As rod-like prismatic crystals, to 0.2mm, elongated and striated k [001], and in grains, to 3 mm
- Twinning: Lamellar in several directions, common
- X-ray powder pattern: 2.98 (10), 2.55 (10), 1.955 (9), 2.61 (8), 2.45 (8), 1.985 (8), 3.09 (7)

Chemical Composition

Elements	Content 1	Content 2
Cu	37.4	37.1
Ag	33.1	33.3
S	17.2	16.9
Hg	14.0	13.8
Total	101.7	101.1

Optical Properties
- Anisotropism: Strong
- R1–R2: (400) — , (420) — , (440) 35.4–30.6, (460) 35.6–31.0, (480) 35.4–31.0, (500) 35.0–30.2, (520) 34.0–28.9, (540) 34.0–28.0, (560) 33.4–27.2, (580) 32.8–26.5, (600) 32.4–26.0, (620) 32.1–25.6, (640) 31.8–25.1, (660) 31.5–24.9, (680) — , (700)

Estimated Properties

Electron density	Bulk density (electron density) = 5.96 g/cm³ note: Specific gravity of balkanite = 6.64 g/cm³
Photoelectric	PE_balkanite = 306.97 barns/electron U = PE_balkanite x ρ electron density = 1,829.83 barns/cm³
Fermion index	Fermion index = 0.03 Boson index = 0.97
Radioactivity	Balkanite is not radioactive

How to Identify Balkanite

Balkanite can be identified in the field by its color variations, such as gray, and steel-gray. Its opaque form has a metallic luster, but no cleavage.

The density of balkanite is 6.318 g/cm³, with a hardness of 3.5 – approximate to a copper penny.

Global Distribution

Balkanite is distributed in the following places:

Bulgaria - In the Sedmochislenitsi mine, Vratsa district, western part of the Stara Planina (Balkan Mountains), Bulgaria
USA - From Manhattan, Nye Co. Nevada
Mexico - From about 20km south-west of Agua Prieta, Sonora

Occurrence of Balkanite and Useful Mineral Association

Balkanite occurs in the Sedmochislenitsi mine, Vratsa district, western part of the Stara Planina (Balkan Mountains).

It is often associated with minerals such as bornite, chalcopyrite, djurleite, digenite, tennantite, stromeyerite, chalcocite, wittichenite, bismuth, rammelsbergite, mercurian silver, mckinstryite, cinnabar, calcite, pyrite, barite, and aragonite.