Diorite
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Diorite is an intrusive igneous rock formed by the slow cooling underground of magma that has a moderate content of silica and a relatively low content of alkali metals. It is intermediate in composition between low-silica (mafic) gabbro and high-silica (felsic) granite.
Orbicular diorite from Corsica (corsite)
Hornblende diorite from the Henry Mountains, Utah, US
Naqada II jar with lug handles; c. 3500–3050 BC; height: 13 cm (5 in); Los Angeles County Museum of Art (US)
Statue of Gudea I, dedicated to the god Ningishzida; 2120 BC (the Neo-Sumerian period); height: 46 cm (20 in), width: 33 cm (10 in), depth: 22.5 cm (8.9 in); Louvre
Intrusive rock
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Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form intrusions, such as batholiths, dikes, sills, laccoliths, and volcanic necks.
Devils Tower, United States, an igneous intrusion exposed when the surrounding softer rock eroded away
An intrusion (pink Notch Peak monzonite) inter-fingers (partly as a dike) with highly metamorphosed black-and-white-striped host rock (Cambrian carbonate rocks) near Notch Peak, House Range, Utah, United States
Dark dikes intruded into the country rock, Baranof Island, Alaska, United States