top of page

Hauyne, Calcite, Gonnardite, Phlogopite - Badakshan, Afghanistan

Haüyne is a very interesting mineral. As are sodalite, nosean, and even lazurite. In fact - they are all pretty much the same and very hard to distinguish from each other. They are all members of the cancrinite sodalite group and even EDS has a hard time telling them apart.

About the blue stuff: Most of the blue minerals from Badakshan are members of the Cancrinite Sodalite Group.

These include the following:

Lazurite: Na6Ca2(Al6Si6O24)(SO4,S,S2, S3,Cl,OH)2 Afghanite: Na22Ca10(Si24Al24)O96(SO4)6Cl6 Haüyne: Na,K)3(Ca,Na)(Al3Si3O12)(SO4,S,Cl Nosean: Na8(Al6Si6O24)(SO4)H2O Sodalite: Na8(Al6Si6O24)Cl2

All of these minerals are often misidentified and confused with each other. The absence of calcium and chlorine (or the presence) is often the only characteristic separating nosean from haüyne for example; in massive form (no crystals) there is little visible difference. Lazurite has more sulfide while haüyne has more sulfate. Minrec reports that most lazurite is really sulfide-rich haüyne. I’m pretty sure much of the massive material also has afghanite thrown in for good measure.

Hauyne and Gonnardite - Fullwave UV (SW+MW+LW)

So - if there are no crystals to help in the identification, the massive blue mineral could be many things. Worse, the fluorescent activators have not been studied from this area and it’s very unclear what is going on. But they sure do make for some confusing but beautiful fluorescent specimens.

The Haüyne fluoresces a burnt orange under LW, phlogopite yellow under SW, the gonnardite is bright under MW and LW, but is fluorescent under all three. The calcite is very bright under both SW and MW. Gonnardite is an alteration product of hauyne and fluoresces a bright white to creamy white under both LW and SW (and MW). You will most often find it associated with hauyne.

A little about lazurite and lapis lazuli: The “real” gemstone lazurite is rarely fluorescent, not translucent and always a deep blue. Lazurite is a tectosilicate belonging to the sodalite group. The main members of the group found in Sar-E-Sang are: sodalite, nosean, haüyne, and lazurite. Lapis Lazuli is a rock - The primary minerals found in lapis lazuli are: sodalite, hauyne/afghanite, pyrite, calcite, phlogopite, feldspars, scapolite, forsterite, nepheline, afghanite, and wollastonite.

The amount of sulfur in these specimens plays an important role in the fluorescence, but I’m sure there are numerous activators that have not been discovered yet. Study is needed on the fluorescence of these minerals. Lucky specimens will have calcite (although the miners do their best to etch the calcite away to reveal the valuable afghanite crystals. Almost always the calcite is a nice orange under SW and MW, strongest MW. Bright yellow fluorescing phlogopite is often found also (SW). In rare cases phlogopite will also fluoresce under MW - a butterscotch color, and sometimes even under LW - just a darker butterscotch.

149 views0 comments
bottom of page