Unique Rock - Fossil, or just cool?

[Kipling79]

This is my first thread, but hopefully not my last. I have always loved picking up unique rocks ever since childhood, but only occasionally finding an obvious fossil.

 

As an adult, I purchased my first home in southern Michigan, which I believe sits atop a moraine. This "moraine" is a 5 acre pile of sand, rocks, and boulders which rises about 40 feet higher than the surrounding fields. 

 

A few weeks ago, I found the pictured stone poking out of one of the slopes. I am fascinated by it, and am curious what it could be. 

 

The stone is triangular, approximately 20" long and 10" thick. The greenish layer visible is only a couple inches thick, with the remainder resembling a red granite. 

 

Aside from the organic feel, I am particularly fascinated by the 5" leaf shape on top with the "Z" inside of it. I just can't picture this being the result of rock formation/erosion.

 

Thanks for any help!

[Kipling79]

Note: The leaf shape that I mention was the only visible portion of the rock until I started digging. I guess it could be a carving, but the raised "veins" do seem to match the veins that were not visible below the sand.

[Darko]

Doesn't look  like a Fossil to me .More like a rock with quartz veins in it.

[Kipling79]

3 minutes ago, Darko said:

Doesn't look  like a Fossil to me .More like a rock with quartz veins in it.

I appreciate the reply. I definitely wanted some opinions before I removed it and set it up by the house.

 

I found this site on my phone, and registered/posted immediately before seeing the posting guidelines. I can edit the post to conform once i get my laptop back (forgot it at work).

[ynot]

Welcome to TFF!

I agree with a rock with mineral veins. The "leaf" shapes are probably fracture structures, but would like to see some close up pictures of them to be sure.

[Kipling79]

Just now, ynot said:

Welcome to TFF!

I agree with a rock with mineral veins. The "leaf" shapes are probably fracture structures, but would like to see some close up pictures of them to be sure.

It is dark now, but will add more pictures tomorrow. Thanks again!

 

Should I add the new pics tothe original post?

[ynot]

1 minute ago, Kipling79 said:

Should I add the new pics to the original post?

Yes, but You can use a reply to this thread.

[goatinformationist]

Welcome to the Forum from sunny Atlanta. 

Win, lose, or draw that is one unique door stopper, worthy of pride of place.

[caldigger]

3 hours ago, Kipling79 said:

It is dark now, but will add more pictures tomorrow. Thanks again!

Come on, wheres your sense of adventure? You get over there with a flashlight clinched in your teeth and get us some up close shots right now!

Our curiosity can't wait till tomorrow.

[Rockwood]

8 hours ago, Kipling79 said:

The greenish layer visible is only a couple inches thick, with the remainder resembling a red granite. 

I suspect the red granite looking material may be a weathered version of the greenish rock.

Shapes like the leaf are sometimes the result of contact with another rock for an extended period of time. 

[Johannes]

The rock is most likely an amphibolite (close ups and fresh berak is needed for a valid macroscopic indentification). The positive relief as a result of weathering follows cracks, where fluids impregnate the rock with more weathering resistant minerals (my guess wolud be impregnation with quartz).

 

Some might say it is decorative, but it is definitly no fossil. You may use it as a paperweight.

[Kipling79]

19 hours ago, caldigger said:

Come on, wheres your sense of adventure? You get over there with a flashlight clinched in your teeth and get us some up close shots right now!

Our curiosity can't wait till tomorrow.

Haha! Well I wasn't that adventurous, but I did have the small adventure of rigging a sled and pulley system for dragging this heavy beast uphill into a flower bed.

 

This thing really looks different out of the ground, and cleaned up. The "leaf" depression is no longer as distinct, but I definitely do like the interface between the green/red layers. 

 

Even if not a fossil, I appreciate all of the effort you guys put into this. Maybe I will have to take this over to a geology forum until I find a true treasure! lol.

 

It is wet here, so I hope the gloss doesn't interfere with visual inspection.

[Kipling79]

Final two pics:

[abyssunder]

Last two pictures remind me of a speleogen like "boxwork".

[DPS Ammonite]

I see the granitic rock with reddish k feldspar, greyish quartz white Na feldspar and some green epidote. The dark rock was probably a mafic volcanic rock. The whole rock looks metamorphosed because it is lineated and has warped bedding.

 

Older metamorphosed cratonic rocks are common in the Canadian Shield from where the glaciers might have brought the rock.

 

The ridges are due to cementation by a hard mineral such as quartz. As for the Z we need to ask Guy Williams if he knows anything about it.

[caldigger]

It does make for a really neat piece of "Yard Art" for the garden.