Phonolite mineral rock crystals, polarised light micrograph. This rock consists of feldspar, nepheline, pyroxene and amphibile minerals. It is an igneous rock, formed when molten volcanic lava solidifies. It often contains larger mineral crystals held within the fine-grained matrix, forming what is known as a porphyritic texture. The name 'phonolite' refers to the ringing sound the rock makes when struck. This sample, 12-15 million years old, is from Hohenkraehen, Hegau, Baden, Germany. Magnification: x40 when printed at 10 centimetres across. | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / EYE OF SCIENCE |
Taille de l’image : | 5622 px × 4016 px |
Model Release : | Non requis |
Property Release : | Non requis |
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