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,
About the value of de-collecting
For the tenth episode of the Stack of Stones community podcast, I sat down with Ed Richard to discuss a topic
Exhibition Pristine Minerals & Stack of Stones
For the international mineral show in Rijswijk, Ed of Pristine Minerals and Rolf of Stack of Stones have put together a special exhibit featuring minerals from India and the pegmatites of Afghanistan and Pakistan.
Ethical aspects of rose quartz mining
On February 10, 2025, consumer TV program Radar paid attention to the extraction and trade of rose quartz in Madagascar, including hidden camera footage of the mineral show in Rijswijk (Netherlands). This led to mixed reactions within the gem industry in the Netherlands. This article discusses the provenance, working conditions and sustainability of rose quartz, focusing on both the specific situation in Madagascar and the broader context within the global mining industry. This provides insight into the challenges and nuances of the gemstone trade. The article has been updated in response to the discussion generated by the broadcast.
Acquisition of the month: Japanese twin quartz
I recently added a fine specimen of a Japanese-law quartz twin to my collection from the Ambolo Quartz Mine in Madagascar.
Tips for visiting a mineral show
Mineral shows are a melting pot of passion, knowledge and discovery. If you have ever visited a mineral show, you know
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
Story behind the stone: sulfur from the Ijen volcano
Recently a friend gave me a beautiful piece of sulfur, he asked me if I knew where it came from, “Indonesia”
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
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. It also looks at a possible related rock from Finland.
Read the article for tips on identifying real nuummite and avoiding misleading simulants. With illustrations to show the differences.
Fascinating Larvikite: Norway’s national stone
Larvikite is known for its unique appearance with changing colors and light effects. Read more about the composition, origin and applications of this special rock from Norway in this article.
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”
Uvite: A rare and fascinating mineral from the tourmaline group
Uvite is a rare and remarkable mineral that is part of the tourmaline group. Unlike the usual elongated crystals characteristic of
Flos Ferri: the delicate and rare form of aragonite
Flos Ferri, or “flowers of iron,” is a unique and rare variety of aragonite. This beautiful form of aragonite occurs in
CAUTION: enforcement law regarding asbestos minerals!
Recently I received a warning letter from the Inspectorate for the Environment and Transport (ILT) of the Ministry of Infrastructure and
Olivine: the versatile green mineral with numerous applications
Olivine is a fascinating and versatile mineral that ranges from forsterite, rich in magnesium, to fayalite, rich in iron. These silicate
Saint Barbara, multipurpose patron saint
Recently I received a beautiful statue of Saint Barbara for my birthday. I already posted the attached photo on social media
Well-known combination of Azurite and Malachite from rare location: Sepon mine in Laos
When collecting minerals, for many not only the species is important, but certainly the location. Sometimes the location is even more
Typical geodes
In this article, we explore the fascinating world of geodes, hollow spaces in rocks filled with beautiful minerals such as chalcedony, agate, and quartz. Well-known examples include the amethyst geodes from Brazil and the Las Choyas “coconut” geodes from Mexico. We also discuss lesser-known but unusual varieties such as the Puma agates and Red Fox agates from Argentina, and the Dugway geodes from Utah, USA. Discover how the locality and composition of geodes give them a unique identity, and learn about the local names and typical features that set them apart.
Progress is impossible without change
New developments are piling up at Stack of Stones. Today, I am pleased to delight you with the first monthly ‘Written
Analysis: Black moonstone
Is ‘black moonstone’ real moonstone? Classic ‘true’ moonstone is mineralogically a combination of orthoclase or microcline with albite (belonging to the
Siccar Point in Scotland: Geological Wonder and Historical Importance
Siccar Point, located on the east coast of Scotland, is an important geological site that has played a crucial role in
Fact or fable? – Septarian concretions originate from deceased animals
Septarian is a special stone that attracts attention with its unique appearance. Moreover, an interesting story circulates about the origin of
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
Analysis: White moonstone
What is white moonstone? There are several different “white” moonstones on the market, which can be, for example, a “real” alkali
Green ‘smithsonite’ from Indonesia appears to be garnierite (falcondoite) in quartz
In 2023, ‘new’ material appeared on the market from Indonesia: green crustal deposits and crystals in fissures in yellow-brown rock. Commonly
Analysis: Pink moonstone
Is pink or peach moonstone also real moonstone? Classic ‘true’ moonstone is mineralogically a combination of orthoclase or microcline with albite
Lewisian Gneiss: The fascinating history of one of the oldest rocks on Earth
The Isle of Lewis and Harris, located in the Outer Hebrides of Scotland, is home to Lewisian Gneiss, one of the
Analysis: Rainbow moonstone
Genuine moonstone or white labradorite? At the bottom of the page you find a summary of the main points of this
Analysis: Green moonstone
Clarity on green color in green moonstone In 2021, I had a tumble stone of “green moonstone with garnierite” analyzed because,
Analysis: Kiwi Jasper
Clarity on composition of ‘Kiwi jasper’ In 2021, I had a number of tumble stones with beautiful names analyzed because I
Analysis: Azumar or Amazonite?
Azumar™ is an unregistered commercial name coined in 2014 by Robert Simmons(Heaven & Earth) and used for material he marketed at
