FMF - Friends of Minerals Forum, discussion and message board

[p2k]

Okay, I've had this rock for well over 5 years. My father's friend gave it to me and claimed he found it outside his home. I have yet to identify it, and haven't found anything matching it through countless image searches.

I really hope someone here can help me identify this rock, it would be greatly appreciated.

Some things about it:

-Greyish-blue colour
-Shiny/Metallic
-NON magnetic
-Slightly melted on one side

Here's some pics:

[Les Presmyk]

Will you knife scratch it? It looks somewhat like bornite. Where did you grow up?

[p2k]

It was found in Ontario, Canada. I tried scratching it and it was very difficult. It's really hard. But from what I can tell the inside remains the same metallic look as the outside.

A couple images I saw on google of Bornite did resemble this quite a bit though. That's probably what it is. Thanks.

But if anyone else has any ideas besides this go right ahead and say it.

[gemlover]

Galena?
Hematite?
Manganite?
Sphalerite?
Arsenopyrite?

Need properties of the sample:
hardness
Specific Gravity
Streak
Cleavage/fracture type

John

[p2k]

Well, I guess the hardness can be determined. I tried scratching it with a knife. Both the knife AND the sample received scratches.

I then attempted to break off a small piece using a hammer, i gave up as i didn't want to end up smashing the whole sample. I did end up hitting the side a few times though, and a chalky metallic dust came off. When i touched it with my thumb, the dust rubbed onto my thumb. It was a dark colour. Nearly black. So I guess that helps determine the streak.

As for the gravity, how would i determine that? The mineral DOES feel quite heavy, especially for it's size.

Also, I don't think I can determine the cleavage without breaking it. Unless it could be determined simply by looking at the pictures. I'm not exactly sure, I haven't tried identifying rocks before.

[p2k]

I think I'll post some additional information if this helps.

Size: 8x5.5cm

There are small holes scattered across the rock.

In the picture labeled '4', you can notice that part of the mineral seems melted. It has a smooth texture opposed to the somewhat rough texture in the rest of the mineral.

I hope this information helps.. I'm just trying to provide as much information as possible so that someone can identify the sample.

I'm leaning towards Bornite right now, but I'm not completely sure.

[Les Presmyk]

Between the holes, the hardness and the melted appearance, it sounds like a smelter product to me.

[Mike P.]

It looks like the sample that I found-Chromine (3)+ Iron

[Joseph DOliveira]

[Joaquin Montoro]

I think it's only speiss, a smelting product containing essentially iron arsenide.
As other times, hard, heavy and silvery bright, so not a mineral but a man made slag.

[Mark Ost]

Looks a lot like specular hematite. Does it streak red?

[John Jaszczak]

Another possibility is (synthetic) silicon.