Arkose is a clastic sedimentary rock that is characterized by its high content of feldspar. This distinguishes it from other sandstones, which typically have a higher proportion of quartz.

Here's a breakdown of the typical mineral composition of arkose:

* Feldspar: 25% or more (typically orthoclase or plagioclase)

* Quartz: 25% or less

* Rock fragments: Typically less than 10%

* Other minerals: May include mica, clay minerals, and heavy minerals like garnet and zircon.

The presence of feldspar in arkose indicates that it was derived from the weathering of granite or other igneous rocks rich in feldspar. The relatively low quartz content suggests that the source rocks were not subjected to prolonged weathering or transportation, which would have allowed quartz to accumulate.

It's important to note that the exact mineral composition of arkose can vary depending on the specific source rocks and the conditions under which the rock was formed. However, the high feldspar content is always a defining characteristic.