<p>Sulfide ore petrography is reflected light is even harder than transmitted light. Unlike transmitted light, colour is actually a very important characteristic feature. But the perception of colour can vary between different light sources, quality and time since polish, microscope lens, and cameras. Therefore, from an image like that it is extremely challenging to tell what the minerals are.</p>

<p>In my opinion you have two of either chalcopyrite, pyrite, pentlandite, pyrrhotite. It is very hard to tell. My guess would be pyrite (the bright one) and chalcopyrite/pentlandite (the golden one).</p>

<p>In cases like this, as a way to move forward, do one or both of the following:</p>

<ol>
<li>Have thin sections where you know the identity of the minerals so you can compare with your unknown, on exactly the same analytical conditions.</li>
<li>Get access to an EDS-SEM system. I know it's easier said than done, but nowadays these instruments are extremely common in almost every research institution, and once you're experienced it takes literally minutes to identify the minerals.</li>
</ol>

CC BY-SA 4.0
2020-02-25T13:01:08.897Z
thanks @Gimelist you are right, there are two ore minerals- pyrite and chalcopyrite.
Lakhwinder Sidhu
CC BY-SA 4.0
2020-02-25T08:22:24.040Z
2020-02-25T08:22:24.040Z
Gimelist
<p><a href="https://i.sstatic.net/WiqZo.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/WiqZo.jpg" alt="polished sample of mineral-rich rock"></a></p>

<p>The following image is of polished sample of mineral-rich rock. There are two major portions we can see that is ore minerals and rest the grayish material is <a href="https://en.wikipedia.org/wiki/Gangue" rel="nofollow noreferrer">gangue</a>. The photo was taken with an ore microscope.</p>

CC BY-SA 4.0
2020-02-24T12:14:39.133Z
Interesting question and cool image! I've made a slight edit to your question. Recently "rock identification" questions have been decided to be off-topic, so to avoid any close votes I modified it to be "What minerals are likely to be found..." and "What can we deduce."
uhoh
CC BY-SA 4.0
2020-02-25T05:18:19.750Z
Can you provide the link where this is discussed?@Universal_learner
Lakhwinder Sidhu
CC BY-SA 4.0
2020-02-25T10:52:07.440Z
@Universal_learner I hadn't seen that, thanks!
uhoh
CC BY-SA 4.0
2020-02-25T18:26:09.223Z
I'm confused about exactly what is being asked.  Do you mean that the mineral(s) naturally occur in thin sections, or that you've prepared a thin section of some specimen and want to know what minerals are there?  Also would be nice to know the magnification.
jamesqf
<geology><rocks><ore>
What ore minerals are likely to be found in a thin section like this? What can we deduce from the structure?
Lakhwinder Sidhu
# What ore minerals are likely to be found in a thin section like this? What can we deduce from the structure?

(Asked by: username_0 on 2020-02-24)

[![polished sample of mineral-rich rock](https://i.sstatic.net/WiqZo.jpg)](https://i.sstatic.net/WiqZo.jpg)

The following image is of polished sample of mineral-rich rock. There are two major portions we can see that is ore minerals and rest the grayish material is [gangue](https://en.wikipedia.org/wiki/Gangue). The photo was taken with an ore microscope.

**Tags:** geology, rocks, ore

> **Comments:**
> **username_1**: Interesting question and cool image! I've made a slight edit to your question. Recently "rock identification" questions have been decided to be off-topic, so to avoid any close votes I modified it to be "What minerals are likely to be found..." and "What can we deduce."  
> **username_0**: Can you provide the link where this is discussed?@Universal_learner  
> **username_1**: @Universal_learner I hadn't seen that, thanks!  
> **username_2**: I'm confused about exactly what is being asked.  Do you mean that the mineral(s) naturally occur in thin sections, or that you've prepared a thin section of some specimen and want to know what minerals are there?  Also would be nice to know the magnification.  

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## 1 answers

### Answer by username_3 on 2020-02-25. Score: 3 | Accepted answer

Sulfide ore petrography is reflected light is even harder than transmitted light. Unlike transmitted light, colour is actually a very important characteristic feature. But the perception of colour can vary between different light sources, quality and time since polish, microscope lens, and cameras. Therefore, from an image like that it is extremely challenging to tell what the minerals are.

In my opinion you have two of either chalcopyrite, pyrite, pentlandite, pyrrhotite. It is very hard to tell. My guess would be pyrite (the bright one) and chalcopyrite/pentlandite (the golden one).

In cases like this, as a way to move forward, do one or both of the following:

1. Have thin sections where you know the identity of the minerals so you can compare with your unknown, on exactly the same analytical conditions.
2. Get access to an EDS-SEM system. I know it's easier said than done, but nowadays these instruments are extremely common in almost every research institution, and once you're experienced it takes literally minutes to identify the minerals.

> **Comments:**
> **username_0**: thanks @username_3 you are right, there are two ore minerals- pyrite and chalcopyrite.  

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