The most common and most likely answer to this crossword clue is the 6 letter word GNEISS
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More clues leading to the result GNEISS
- Rock that’s good to listen to
- Rock singer’s run off, rocking
- Carelessly singes coarse-grained rock
- Granite-like rock in Dordogne is spectacular
- Rock agreeable to an audience
- Rock and roll primarily lacking in training of singers
- Rock singers wanting Queen to reform
- Badly singes rock
- Rock can be kind on the ear
- Rock that’s pleasant to listen to
Buddy explains!

The straight part
We know that "coarse-grained rock" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case coarse-grained rock = gneiss.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GNEISS mean?
GNEISS noun- A common and widely-distributed metamorphic rock having bands or veins, but not schistose.