70157 (4) High-Ti Mare Basalt
We would like to thank the following for the use of this sample:
70157 is a medium grey, sub- to intergranular basalt with one miarolitic cavity that was collected from a basaltic boulder named the "Geophone Rock". It is a plagioclase-poikilitic basalt. Anhedral and blocky ilmenite forms an intersertal texture with pyroxene and plagioclase feldspar. Ilmenite contains rutile and spinel exsolution lamellae. Armalcolite is present as ilmenite-free inclusions in pyroxene. Olivine forms small inclusions in pyroxene and plagioclase (rotation 1). Metallic iron and troilite are interstitial phases. No discrete spinel minerals are present. Olivine exhibits moderate variation, although individual grains are usually homogeneous. Plagioclase shows little zoning or inter-grain variation (An 84-89). Pyroxene compositions exhibit little Fe enrichment, although there is a continuum of compositions between titanaugite and pigeonite.
The sample weighed 0.57 grams before analysis and has not been dated.
Further details of this and other Apollo samples are here: http://curator.jsc.nasa.gov/lunar/
Ma = Millions of years ago
Rock forming mineral:
- metallic iron,