67455 (105) Anorthositic Breccia
Collection:
Click the microscope button to view a thin section for this sample.
Microscope
Click the microscope button to view a thin section for this sample.
Microscope

Fact sheet

67455 (105) Anorthositic Breccia

67455 is a very friable, white polymict feldspathic breccia that was collected from the top of a large boulder on the rim of North Ray Crater. It is a highly-shocked, fragmental-matrix breccia and contains clasts of various cataclastic anorthosites. The groundmass of 67455 is made up of crushed and compacted plagioclase grains (rotation 2). Within the crushed matrix are numerous clasts of weakly shocked, cataclastic anorthosite with relic cumulate texture. Mineral chemistry indicate they are ferroan anorthosite. Metallic iron and sphalerite are present as accessory minerals.

The sample weighed 942 grams before analysis. Pristine anorthosite clasts in this fragmental breccia have been dated at 3.91±0.12 to 3.97±0.021 billion years (Ar/Ar).

Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/

Our thin section is slightly thick in parts. Laser or SEM analysis lines criss-cross the sample.
 

About this collection

The Apollo 16 landing site was in the hilly region around Descartes crater in the lunar highlands. The landing spot was chosen to allow the astronauts to gather geologically older lunar material (Descartes Formation and the Cayley Formation) than the samples obtained in the first four landings, which were in or near lunar maria.

The mission lasted 11.1 days, with a stay on the lunar surface of 71 hours. The crew were on the lunar surface for 20.2 hours during which they traversed approximately 27 kilometers and collected approximately 96 kilograms of samples.

Apollo 16 was launched on 16 April 1972.

Sample details

Collection: Apollo 16
Type
metamorphic
Rock-forming mineral
pyroxene
plagioclase
feldspar
Accessory minerals
sphalerite
metallic iron
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: