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What type of ore deposit does this rock best represent?

A rock with a porphyritic texture is cross cut by a stockwork of quartz veins. Bordering the veins is extensive alteration of the host rock. The vein contains fine-grained (~1mm) chalcopyrite and molybdenite.

I believe it to be a hydrothermal ore deposit as porphyry ore formation, stockwork and the Cu-Mo-Au element list indicates.

Is this a correct line of thinking and if so is it specific enough, do you think?

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  • $\begingroup$ Is this simply a hydrothermal - porphyry - type ore deposit? $\endgroup$
    – Edward
    Mar 16 at 14:08
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    $\begingroup$ It is indeed, however, per my comment above, I am meerly seeking confirmation that it is simply a hydrothermal ore deposit @JeopardyTempest $\endgroup$
    – Edward
    Mar 16 at 15:02
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    $\begingroup$ It'd be good to put that in the question itself... and a short thought on why you go in that direction :-) $\endgroup$ Mar 16 at 15:07
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    $\begingroup$ @JeopardyTempest Amended I believe :-) , do let me know if there is anything else as I am very new to this site. $\endgroup$
    – Edward
    Mar 16 at 15:12
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    $\begingroup$ Looks good, hope you get a good response, and that you can find places to contribute as well! :-) $\endgroup$ Mar 16 at 15:45
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This is the classic description of a porphyry copper-molybdenum deposit.

What happens is that there is a magmatic intrusion (the porphyry), which then solidifies. When it solidifies, it expels acidic hydrothermal fluids which carry metals in them - most often copper (represented by chalcopyrite) but also sometimes molybdenum (represented by molybdenite).

Once the fluids hit solid rocks, they react with it, and become neutralised. The carrying capacity of the fluids diminish, and they deposit the metals into the minerals you observe. The solid rocks can be pretty much anything. It can be the porphyry itself, another porphyry that happened to be around, sedimentary rocks, or whatever.

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