Can you help me with rock identification? (Metamorphic)

[rn18]

I'm currently taking Physical Geology course. Please help me to identify these 2 rocks: A & B.

*Both rock are cracked open.





I am sure that rock A is a metamorphic rock & rock B is the protolith of rock A. But what are the names of the two rocks?

Overall, my questions are:

1. What is the name of the rock (A & B)?

2. What are the dominant minerals in rock A & rock B? (eg. Quartz, biotite, calcite, etc.)

3. What processes were responsible for creating rock A & rock B?
•If metamorphic, describe what the rock was prior to metamorphism and speculate on what forces may have caused it to metamorphose (continental collision, meteor impact, igneous intrusion, etc.).


Thank you

 

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[Eu_citzen]

Identifying rocks over images is near impossible. Instead ask yourself the question: What's it made of?

To me, it looks like quartz. Check under magnification to confirm. If uncertain, hardness test with knife! (remember: Quartz is 7 on mohs!)
Which would make Sandstone & Quartzite likely candidates.

So, what forms sandstone? Well, sand, making it a clastic rock.
Pressure does the rest which includes precipitates some minerals in the pore-spaces effectively "glueing" the rock together.

If subjected to heat and/or hydrothermal alteration, quartzite may form. (double check in your litterature!)

 

[DDancer]

Rock A is what I will call a quartz cobble. Possibly rose quartz however the coloration may be a mineral inclusion as it appears to have leached out of the rind of the stone. Rock B has no definition in the photo's for me to guess at what it is other than to look like a silicate of some sort. You'll have to state why you feel its a protolith and define its characteristics as well as where it was recovered and the geology that it was recovered from.
As to the processes which formed them again you would have to state the origins of the stones as there are a few process's that can form them.

 

[DizzyDigger]

I'm currently taking Physical Geology course. <snip>
Thank you

Not to be rude, but people never learn a thing by having other people do their
homework for them, and that's exactly what you're asking us to do for you.

How about this: What do YOU think the answers are to the questions you asked,
and then we can discuss your answers, and why they may be right, or wrong?

That way we all learn something..