A few gwindel specimens have been found at the hyalophane occurrence of Busovaca, Bosnia-Herzegovina (Zorz, 1996, 2002) and near the villages of Budinarci and Mitrasinci near Berovo, Macedonia (Zorz, 2002).
(1996) The hyalophane occurrence at Zagradski Potok near Busovaca, Bosnia and Hercegovina.
The specimens in the other cases were from several prominent Italian and French collections, and included, as might be expected, a stunning selection of quartz specimens, in particular gwindels and faden crystals, as well as pink fluorites and a few less common species such as a 5-cm hyalophane
from Trou des Romains, Aosta Valley (R.
occurs as oscillatory zoned phenocrysts and rims on sanidine and anorthoclase phenocrysts in plagioclase phonolite (Birmingham, 1987).
Lenz [square] v.27/n.4 Rio Tinto Mines (Spain), Mendip Hills (England), Calcioaravaipaite (AZ) [square] v.27/n.5 Hyalophane
(Bosnia), Red Cloud Mine Wulfenite Discovery (AZ), N.
The FM award for best article of the year in the Mineralogical Record went to Mirjan Zorz for "The Hyalophane
Occurrence in Bosnia-Herzegovina." For the Rocks & Minerals FM award the article chosen was "Colorado Topaz" by Peter J.
Petersen and Karsten Secher, "The Minerals of Greenland" (Mar/Apr) 1994 Ulrich Burchard, "History and Apparatus of Blowpipe Analysis" (Jul/Aug) 1995 Michael Menzies, "The Mineralogy, Geology and Occurrence of Topaz" (Jan/Feb) 1996 Mirjan Zorz, "The Hyalophane
Occurrence at Zagradski Potok near Busovaca, Bosnia and Hercegovina" (Sept/ Oct) 1997 Alan Goldstein, "The Illinois-Kentucky Fluorite District" (Jan/Feb) 1998 Thomas Moore, Bryan K.
The Baumann prospect, once explored for its barite potential in the late 1920's, hosts a number of barium minerals including alforsite, barite, bazirite, benitoite, celsian, fresnoite, hyalophane, krauskopfite, macdonaldite, sanbornite, titantaramellite, walstromite, witherite and two new minerals which are currently under study.
A study of our specimens collected from the metasediments has revealed the presence of alforsite, benitoite, bazirite, hyalophane, macdonaldite, walstromite and two new barium silicate minerals which are Fe and Mn analogs of each other.
Among them: tenorite, "illite" and zinnwaldite (from basalt cavities in the Molana quarry), hyalophane
(adularia-like crystals associated with barite), marokite and "axinite" (a group name; actually only two members of this group, manganaxinite and tinzenite, are reported from Val Graveglia).
The Zagradski Potok hyalophane
occurrence has produced huge, lustrous, complexly twinned crystals which are easily the best known examples of the species.
I did find an occasional error - silver is isometric, not hexagonal, and hyalophane
contains barium - but overall, it is an excellent addition to the program.