Provide a detailed rock description. Must include: - Modal minerology (e.g. 35%

Question

Provide a detailed rock description.

Must include:

- Modal minerology (e.g. 35% quartz, 25% plagioclast etc.),

- Detailed description (e.g. Sample X1 is a light-coloured rock, with pinkish K-feldspar crystals. The sample is coarse grained (grainsize range: 2-10 mm), phaneritic, and has a weakly porphyritic texture, with K-feldspar phenocrysts being larger than the other minerals on average. Plagioclase, K-feldspar and biotite exhibit subhedral microstructures, quartz is anhedral. The rock exhibits no obvious metamorphic fabrics (foliation is absent)

- other features

- A Rock name

Explanation / Answer

Modal Mineralogy: Alkali feldspar 70%, quartz 20%, plagioclase 5%, biotite 5%.

Detailed description of the rock:

The rock is mafic.

It is course grained.

The rock is phaneritic, i.e. coarse crystals are visible to the human eye.

Phaneritic texture observed in some places.

Name of the rock: Granite.

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