Photos of euhedral crystals in igneous and metamorphic rocks. Click on any photo for a larger image. Some of the larger images may be on other web sites and will open in a new window.

Andesite cut stone photo

euhedral_001. Cut surface of an andesite from Quito, Ecuador. Rectangular white plagioclase and prismatic black hornblende phenocrysts stand out in a reddish tan groundmass. The plagioclase crystals average about 5 mm across.

Granite outcrop photo

euhedral_002. Large (cm-sized) euhedral alkali feldspar crystals stand out among smaller quartz and biotite grains in this photo of the 540 Ma Peninsula Granite near Cape Town, South Africa.

						Glaucophane Schist Outcrop Photo

euhedral_003. Euhedral (diamond shaped cross section), white lawsonite crystals grew in this glaucophane schist from northwestern Syros, Greece. Although the lawsonite has been replaced by a very fine-grained mixture of other minerals, the euhedral shape of the original lawsonite remains as a pseudomorph. The pseudomorphs are 8-10 mm across.

						Euhedral Staurolite crystals in schist

euhedral_004. Euhdral brown staurolite crystals in a muscovite-quartz matrix have smooth, prismatic faces. Blue-gray kyanite laths and some of the red garnet crystals also show euhdral forms in this photograph of a Gassetts schist outcrop near Ludlow, VT, USA. The larger staurolite crystals are about 2 cm long.