Grossular-prehnite skarn
Collection:
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Microscope
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Microscope

Fact sheet

Grossular-prehnite skarn

Darwin wrote "Various curious minerals, chiefly garnets etc. occurring in three varieties of rock. (Miller says has much appearance of prehnite)"

A complex assemblage containing euhedral, zoned grossular garnet bound together by angular crystals of prehnite. Unusually the garnet is non-isotropic in places. Collected Dec 1832 - Feb 1833.

Additional images
  • Grossular-prehnite skarn
  • Grossular-prehnite skarn
  • Grossular-prehnite skarn
  • Grossular-prehnite skarn
Map
-55.736389, -67.456055
Description:
Wollaston Island, Tierra del Fuago
Precision:
Moderate
About this collection

This collection was a collaboration between The Open University and the Sedgwick Museum, created in 2009 to celebrate the bicentennial of the birth of Charles Darwin.

The Sedgwick Museum opened a new gallery, 'Darwin the Geologist', and created a museum-based virtual microscope to showcase rocks he collected during the Voyage of the Beagle. We enjoy this collection because Darwin did not always pick up a representative sample from the islands he visited; it's often the unusual rocks that caught his eye. Just explore the collection and you'll see what we mean. For those who have the opportunity, a visit to the museum is strongly recommended.

Sample details

Type
metamorphic
Category
skarn
Rock-forming mineral
grossular garnet
prehnite
Category guide  
Category Guide
Title
Refers to any word or phrase that appears in the individual rock names. Names are generally descriptive; they allow users to search for broad terms like ‘granite’ as well as more specific names such as ‘breccia’. However, the adjacent descriptions of the specimens captures a wider range of general words and phrases and is a more powerful search tool.
Description
Refers to any word or phrase that appears anywhere in the descriptions of the specimens
Accessory minerals
Minerals that occur in very low abundance in a rock. They are usually not visible with the naked eye and contribute perhapssver, they often dominate the rare elements such as platinum group metals.
Rock-forming minerals
Minerals that make up the bulk of all rock samples and are also the ones used in rock classi?cation.
Timescale
Selecting one or more period, for example 'Jurassic'.
Theme
A term used to group together related samples that are not already gathered into a single Collection. For instance, there is a ‘SW England granites’ theme that includes such rock types as granite, hydrothermal breccia, skarn and vein samples.
Category
A general term used to label a rock sample. It is a useful way of grouping similar samples throughout a collection. Category names are often, but not exclusively, common rock names (e.g. granite, basalt, dolerite, gabbro, greisen, skarn, gneiss, amphibolite, limestone, sandstone).
Owner
The owner of the sample that appears in the collection. For example, NASA owns all the samples that appear in the Moon Rocks collection
We would like to thank the following for the use of this sample: