Hyalophane

Hyalophane Zagradski Potok mine – Zagradski Creek – Busovaca – Zenica-Doboj Canton – Federation of Bosnia and Herzegovina Overall size:mm. 40 x 33 x 22 © minservice

Chemical Formula: (K,Ba)[Al(Si,Al)Si2O8]
Locality: Imfield, Switzerland.
Name Origin: From the Greek hyalos – “glass” and phanos – “to appear.”
Hyalophane or jaloallofane is a crystalline mineral, part of the feldspar group of tectosilicates. It is considered a barium-rich potassium feldspar. Its chemical formula is (K,Ba)[Al(Si,Al)Si2O8], and it has a hardness of 6 – 6½. The name hyalophane comes from the Greek hyalos, meaning “glass”, and phanos meaning “to appear”.

An occurrence of hyalophane was discovered in 1855 in Lengenbach Quarry, Imfield, in the municipality of Binn, Switzerland. The mineral is found predominantly in Europe, with occurrences in Switzerland, Australia, Bosnia, Germany, Japan, New Jersey, and the west coast of North America.

Physical Properties

Cleavage: {001} Perfect, {010} Imperfect
Color: Colorless, Yellow, White, Red.
Density: 2.81
Diaphaneity: Transparent to translucent
Fracture: Brittle – Generally displayed by glasses and most non-metallic minerals.
Hardness: 6-6.5 – Orthoclase-Pyrite
Luminescence: Non-fluorescent.
Luster: Vitreous (Glassy)
Magnetism: Nonmagnetic
Streak: white

Photos:

Hyalophane Zagradski Potok mine – Zagradski Creek – Busovaca – Zenica-Doboj Canton – Federation of Bosnia and Herzegovina Specimen weight:225 gr. Crystal size:mm. 60 Overall size: 73mm x 33 mm x 60 mm © minservice
Hyalophane var. Manebach-twin Locality: Zagradski Poptok Mine, Busovaca, 50 km northwest of Sarajevo, Bosnia-Herzegovina Overall Size: 4x4x3 cm Crystals: 1-4 cm © AllMinerals/JohnBetts-FineMinerals
The sample is about 12×8 cm and is from Bustovata, Bosnia and Herzegovina. These samples are displayed in the Smithsonian Museum of Natural History.
Hyalophane Zagradski Potok Mine Busovaca Bosnia-Herzegovina  Size: 6x5cm © Webminerals
Zagradski Potok Mine, Zagradski Creek, Busovača, Central Bosnia Canton, Federation of Bosnia and Herzegovina, Bosnia and Herzegovina © fabreminerals