70215 (306) Mare Basalt
Click the microscope button to view a thin section for this sample.
Click the microscope button to view a thin section for this sample.

Fact sheet

70215 (306) Mare Basalt

70215 is a dense, fine-grained porphyritic mare basalt that has been used to create “touchstones” for public display. It was collected near the Lunar Module and is one of the largest stones returned from the Moon. It has variously been termed a “fine-grained, subvariolitic basalt”, “spherulitic, fine-grained high-Ti basalt”, “Type 1A, Apollo 17 high-Ti basalt”, “fine-grained porphyritic basalt” and “medium dark grey, fine-grained basalt”. 

Our thin section consists of phenocrysts of olivine and ilmenite in a groundmass of fan-shaped intergrowths of plagioclase and pyroxene. The olivine displays a variety of shapes including elongate, hollow prisms, equant and subequant grains and skeletal, euhedral phenocrysts. Ilmenite phenocrysts occur as equant grains and as laths with irregular jagged edges which commonly contain cores of armalcolite and lamellae of rutile. The groundmass contains minute bow-tie intergrowths of plagioclase and pyroxene along with needle-like laths of ilmenite. Troilite and metallic iron occur in the groundmass.

The sample weighed 8110 grams before analysis. It has been dated at 3.85±0.08 billion years (Rb/Sr).

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

Note the thin section is slightly thick.

About this collection

Apollo 17, the final manned landing mission, had two objectives: to obtain samples of ancient rocks from the lunar highlands and to look for evidence of younger volcanic activity on the valley floor.

This small Collection contains material deriving from both periods, including igneous rocks around 4.3 billion years old from the lunar highlands as well as younger volcanic samples dating from about 3.6 billion years ago.

Apollo 17 was launched on 7 December 1972.

Sample details

Collection: Apollo 17
Rock-forming mineral
Accessory minerals
metallic iron
Category guide  
Category Guide
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.
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.
Selecting one or more period, for example 'Jurassic'.
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.
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).
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: