Geological George - Education and Activities , UncategorizedGeological George - Education and Activities , Uncategorizedhttps://www.geologicalgeorge.com/blogs/UncategorizedWed, 29 Apr 2026 22:47:07 -0700http://zoho.com/sites/<![CDATA[Australian Meteorite ]]>https://www.geologicalgeorge.com/blogs/post/AustralianmeteoritesA short introduction to Australian Henbury Meteorites]]>

Meteroites from the Henbury Crater, Northern Territory

Guess what we have! We managed to secure a small number of Australian Henbury meteorites from an old collection. We will be releasing these soon-ish.

These meteorites are an Iron IIIAB, octahedrite (this refers to the internal crystal structure) meteorite consisting of 90% iron and 8% nickel.
Around 4700 years ago the meteorite broke up during entry with the fragments impacting in the Henbury Station in the Northern Territory, roughly 130km south of Alice Springs. The impact made 13-14 impact craters that range in size from approximately 7-180m in diameter. The impact then ejected meteorite fragments into the surrounding area. Significance of the site was realised in the 1930's when a survey of the site was conducted.

As the impact occurred during recent times it appears to have been witnessed, with Aboriginal traditions describing "… a fire debil-debil (evil spirit) came out of the sky and killed everything in the vicinity.". An impact of this scale would have indeed been devastating to anything in the area!
We often get people bringing in ironstone pisolites/nodules asking if they have found a meteorite. These can be mistaken for iron meteorites as they look similar, however the weight and surface texture is different between the two.
]]>Wed, 29 May 2024 11:48:12 +1000<![CDATA[Smokey Quartz....and more]]>https://www.geologicalgeorge.com/blogs/post/Unusual-smokey-quartz-with-epidoteThese are intersting specimens we sourced from Shandong, China. They are smokey quartz crystals with elongate plagioclase crytals on a pink granite matrix. There is also a small amount of epidote crystals.]]>

We take a look at one of the Shandong crystal specimens

These are intersting specimens we sourced from Shandong, China. They are smokey quartz crystals with elongate plagioclase crytals on a pink granite matrix. There is also a small amount of epidote crystals.

]]>Thu, 16 Nov 2023 14:43:36 +1100<![CDATA[Why does this Amethyst look weird?]]>https://www.geologicalgeorge.com/blogs/post/unusual-amethyst-crystal-shapeThe crystals shape on this amethyst looks very unusual. Our Geologist George investigates why. Learn about crystals with a geologist!]]>

We investigate why the crystal structure of this amethyst looks weird

We take a geological look at why this amethyst looks a little...odd.

]]>Thu, 16 Nov 2023 14:15:26 +1100<![CDATA[Check this out!]]>https://www.geologicalgeorge.com/blogs/post/El-Hammom-SpecimenExplore this incredible El Hammom mineral specimen, with calcite crystals, pyrite and more!]]>

An amazing El Hammom specimen

El Hammam is known for producing some very interesting mineral combinations, including quart calcite fluorite barite and various oxides. This specimen is an excellent example of what can come from this site. One side consists of calcite crystals and the other quartz crystals. 

The calcite has inclusions where pyrolusite has grown over the calcite crystals, with the calcite continuing to grow and some covering the pyrolusite while others still have exposed or partially exposed pyrolusite. Then a growth of pyrite covers some of the calcite.

 The quartz has a coating of siderite giving it a golden-brown colour. There is further botryoidal pyrolusite growing over small patches of the quartz. There is also a small additional growth of calcite that is free from and iron and manganese.

THIS SPECIMEN WAS LISTED 17/8/23 and may (or may not) have been sold

]]>Thu, 17 Aug 2023 14:21:13 +1000<![CDATA[Is It Sphalerite?]]>https://www.geologicalgeorge.com/blogs/post/SpaleriteFor about a year now we've been seeing "sphalerite" generators, towers, spheres and cubes. But what are they really?]]>

We test 'sphalerite' to see what it really is

For the last year we've seen 'sphalerite' generators, spheres and geodes. But we've had our doubts...

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