Unknown rock

[Eu_citzen]

Here's one which has me scratching my head for some time. Only just now decided to post.

The general Hardness is around 3-5, don't recall right off hand.

No cleavage can be seen on the bright orange stuff. Has an earthy appearance.
Also very soft 3-4, reacts vigorously with acid.

The green stuff is fibrous and might have cleavage. (to small to tell even with the loupe)

The brown stuff is feldspar-ish. Don't recall off hand how the cleavage is, but there is one present.

I'll update what I don't recall right now.
Oh, and it reacts with HCl.

This is the best pic I could do right now.
The colour is pretty accurate, the red stuff is in reality a tad more towards a bright orange.


Found in southern Sweden. Seems poor in silica? Unusual for being found in the TIB. (transscandinavian igneous belt)

 

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[Turkısh Man]

I think red granite marble.

 

[Diggin-N-Dumps]

Looks like my parents countertop...which is Red Granite

 

[Eu_citzen]

Seen plenty of marble and granite, this is not one. I intend to loupe one piece soon.

 

[unclemac]

pink granite ...Ontario is covered in it.

 

[nomad1]

looks like granite but hardness is way off. Granite is around 7.

 

[unclemac]

the older the granite the softer it is....very very old granite crumbles in your hands....

 

[Brian T. Booth]

the older the granite the softer it is....very very old granite crumbles in your hands....

You are talking about weathered granite. That's a rock type called arkose.

 

[Eu_citzen]

This is not granite, nor related to it.
This holds no quartz, no biotite/mica.

However, something feldspar-ish is present.
I'm not really sure what kind it is. Feldspars are not my strong point.

 

[unclemac]

a better picture of the whole thing would help....

 

[mamabear]

am watching this one. I'm sure granite was the first thing you thought of. So if it's puzzling you, it must be good. Am anxious to see what it is. EU, I love your posts.

 

[Brian T. Booth]

Here's one which has me scratching my head for some time. Only just now decided to post.

The general Hardness is around 3-5, don't recall right off hand.

No cleavage can be seen on the bright orange stuff. Has an earthy appearance.
Also very soft 3-4, reacts vigorously with acid.

The green stuff is fibrous and might have cleavage. (to small to tell even with the loupe)

The brown stuff is feldspar-ish. Don't recall off hand how the cleavage is, but there is one present.

I'll update what I don't recall right now.
Oh, and it reacts with HCl.

This is the best pic I could do right now.
The colour is pretty accurate, the red stuff is in reality a tad more towards a bright orange.
http://s1209.photobucket.com/user/V...a/Geology/bergarter059_2_zps115bd771.jpg.html

Found in southern Sweden. Seems poor in silica? Unusual for being found in the TIB. (transscandinavian igneous belt)

The more I look at this photo the more it looks to be a granite. Black in it resembles biotite a variety of mica, but from what I read, what I interpret as black is really green. But if it " reacts vigorously with acid" then I would have to say the mineral(s) within the rock contains some type of carbonate. With that said if the Orange to orangish red color mineral is a carbonate. It could contain aragonite. Ummmm.....if it violently reacts to acid.....has to contain carbonate. My Final answer is some type of marble.

 

[Eu_citzen]

Well had the joy of looking and louping it again today. Seems I will have to make corrections.

What looks black is a really really dark green.
It could be mica, the crystals are to small to tell; even through the loupe.

Now to the orange stuff..
The hardness of the orange stuff is 4 to 4½ in hardness.
Vitreous lustre, no cleavage visible. Does not react with acid. (although I have older pieces which have been etched?)

Either way, I think the best way might be to send it to the Swedish geological survey or a local geologist and get a second opinion. As the finder, I'm finding (pun intended) myself a bit biased this time around. (only because I've never seen such a rock here before)

 

[mamabear]

good idea EU. Let us know the results.

 

[pat-tekker-cat]

eu citizen, I thought you knew ALL your rocks. You and the turkman are really good and I have long admired your work with your stones.

I have a pink heart, that has that green through it, also. I keep forgetting the name of the rock.......
rhodochrosite. could that be it? The mohs hardness seems to be bout right, 3.5 to 4.

Rhodochrosite - Wikipedia, the free encyclopedia

a yahoo or google pic/image search, you will see specimens ranging from low end(heavily included/trash like) to very high end, clean clear material, worthy of faceting.

 

[pippinwhitepaws]

Minerals - Geological Survey of Sweden

 

[Eu_citzen]

If I remember, I'll keep ya updated. They are likely on vacation right now.
I know some of the guys from the geological survey of Sweden.

Pat, No, not really all of them.

It's really the name of the rock that interests me, it consists of several minerals.
Don't think Rhodonite nor Rhodochrosite are part of it. But hey - We'll see.

 

[Brian T. Booth]

If I remember, I'll keep ya updated. They are likely on vacation right now.
I know some of the guys from the geological survey of Sweden.

Pat, No, not really all of them.

It's really the name of the rock that interests me, it consists of several minerals.
Don't think Rhodonite nor Rhodochrosite are part of it. But hey - We'll see.[/QUOTE

If the green mineral is fibrous that could possibly be riebeckite.

 

[Brian T. Booth]

If I remember, I'll keep ya updated. They are likely on vacation right now.
I know some of the guys from the geological survey of Sweden.

Pat, No, not really all of them.

It's really the name of the rock that interests me, it consists of several minerals.
Don't think Rhodonite nor Rhodochrosite are part of it. But hey - We'll see.

If the green mineral is fibrous that could possibly be riebeckite.

 

[Eu_citzen]

That would fit, Brian.