Alkali feldspar granite Alkali feldspar granite Alkali feldspar granite, some varieties of which are called 'red granite', is a felsic igneous rock and a type of granite rich in the mineral potassium feldspar (K-spar). It is a dense rock with a phaneritic texture. The abundance of K-spar gives the rock a predominant pink to reddish hue; peppered with minor amounts of black minerals. As shown in the QAPF diagram, alkali feldspar granite contains between 20% - 60% quartz. Less quartz content would lead to "quartz alkali feldspar syenite". More than 90% of the total feldspar content is in the form of alkali feldspar.
Granite Island (Michigan) is made available to the NMU English Department for creative writing retreats. Granite Island (Michigan) Granite Island is a island in Lake Superior located about northwest of Marquette in the Upper Peninsula of the U.S. state of Michigan. Built upon it is the Granite Island Lighthouse, also known as Granite Island Light Station, "one of the oldest surviving lighthouses on Lake Superior". It is part of Marquette Township, in Marquette County. The island is granite rock that rises nearly perpendicularly to above the surface of Lake Superior, surrounded by deep water. The Native Americans called the island "Na-Be-Quon". That apparently