Controversy surrounding purple fluorite on quartz from China
Since the publication of the first version of this article on Jan. 6, 2026, much new information has become available in a short period of…
Category: Deeper analysis
Remarkable quartz with citrine color from Morocco
For several years, remarkable shaped quartz crystals have been popping up on the market from Morocco with a distinctive citrine color, ranging from yellow-brown to…
Batu Pasir Intan (“diamond sandstone”)
Local name for an unusual sandstone that appeared on the Dutch market in 2024 through a seller with connections in Indonesia. The name literally means…
Analysis: apatite in cleavelandite or not?
By now there are a lot of stones on the market with blue spots, under a lot of different names. One name that has recently…
Analysis: Siberian blue quartz
Siberian blue quartz turns out to be ordinary glass! In July 2021, I had a piece of “Siberian blue quartz” analyzed in a laboratory to…
Analysis: Nuummite
Find out all about Greenland nuummite and similar rocks! Learn how to recognize real nuummite and how to distinguish lookalikes from China and India. …
Sphalerite or not? Part II
In my earlier article sphalerite or not? Part I you could read, which I told about some polished towers of “sphalerite” that I analyzed for…
Analysis: Black moonstone
Is ‘black moonstone’ real moonstone? Classic ‘true’ moonstone is mineralogically a combination of orthoclase or microcline with albite (belonging to the group of alkali feldspars),…
Sphalerite or not? Part I
Quite some time ago I received from one of my students who also sells stones a number of polished towers of “sphalerite.” At least under…
Analysis: White moonstone
What is white moonstone? There are several different “white” moonstones on the market, which can be, for example, a “real” alkali feldspar moonstone, an albite…
