FMF - Friends of Minerals Forum, discussion and message board

[stoner]

Hidden in the heart of Central Europe lies a lesser-known but truly magical location for mineral lovers – the countryside near Kolín, Czech Republic. Here, collectors occasionally uncover a rare and mesmerizing form of quartz known as Star Quartz (also called asteriated quartz).

In this video, you’ll get to see the actual location where these stunning specimens are found, including the exciting moments of discovery. Later, the freshly cleaned and carefully photographed samples are shown in their full beauty, ready to be admired and appreciated.

So sit back, relax, and enjoy this journey into the mineral-rich heart of the Czech lands. 🌍✨

https://www.youtube.com/watch?v=cyJkvVg53vg

[Bob Morgan]

These are so interesting and unique. This is the only instance I know of where quartz takes such development. These appear to be spherules, like that of other minerals. Is there any explanation for how these formed?

[alfredo]

This is a piece of star quartz I got at the Prague show several years ago. Seems to have started growth as quartz with red hematite inclusions, and later continued growth as yellow quartz with probably goethite inclusions. The black mineral is micro-lamellar hematite crystals. There seem to be more than one locality for star quartz in Bohemia. I'm curious whether the local geology differs between the localities, or is the same?
(The quartz looks wet in this admittedly poor photo, but it is in fact dry and just has a peculiarly greasy luster.)

[Herwig]

Nice specimen, Alfredo!

It seems that star quartz is not that unique: it has been found in many different countries.
(mindat has photos of such specimens from 9 different countries).

Here is the mindat gallery for this type of quartz:
https://www.mindat.org/gallery.php?min=398