Amygdaloidal basalt (igneous rock), Romania

3D ModelNoAI

Locality: Romania

Size: 7 cm x 6 cm x 4 cm

Type: Igneous extrusive (volcanic) rock

Description: Basalt is a fine-grained volcanic rock consisting predominantly of plagioclase (P), pyroxene, ± opaque minerals (magnetite, ilmenite). In terms of texture, basalts are usually hypocrystalline, aphanitic, and commonly porphyric. Magmas generally contain dissolved gas, which can form bubbles in the magma as the pressure is released on eruption. These bubbles can get trapped in the solidified rock. After some time, groundwater or hot solutions connected with the volcanic activity pass through the porous lava and deposit quartz, calcite or other minerals. Filled cavities in lavas are called amygdales, and a rock full of them can be called amygdaloidal.

Essential minerals: plagioclase, mafic minerals (like pyroxenes, hornblende and/or biotite)

Non-essential minerals: hornblende, biotite and/or pyroxenes

Website: http://geology.uaic.ro/muzee/mineralogie/

Concept & 3D-modelling by dr. Andrei Ionut APOPEI