Monzonite
“Halfway between granite and gabbro”
Monzonite is a coarse-grained intrusive igneous rock that sits compositionally between granite and gabbro, with roughly equal amounts of plagioclase and alkali feldspar and relatively little quartz. Several famous landmarks are carved from this durable, attractive stone.
plagioclase feldspar, alkali feldspar, hornblende, biotite, augite, quartz (minor)
Monzoni Mountains (Italy), Little Cottonwood Canyon (Utah, USA), Montana, Corsica (France), Scotland
6-6.5
The quartz monzonite from Little Cottonwood Canyon was used to build the Salt Lake Temple — each massive block was hauled by oxen over 20 miles to the construction site.
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