Dense rock formed of compacted crystals

[georgiagirl23]

Attached is a picture of a rock that I found in the North GA mountain area. The outside of the rock is a reddish, light tan color. The inside is mostly dark gray crystals, with some clear, red, and green. While not a heavy rock, it is very dense and extremely hard to break open. I have found many of these rocks, some with protruding, red crystals. I will post pics of that rock this afternoon. Any ideas as to the identification of this rock would be greatly appreciated.

 

[BosnMate]

Looks like granite to me.

 

[Charlie P. (NY)]

Maybe a geode.

 

[Back-of-the-boat]

I agree with Charlie looks like a solidified geode, no cavity.

 

[nuggy]

Nope pretty sure that's granite - igneous rock formed mostly of crushed quartz - Granite, which makes up 70–80% of Earth's crust , is an igneous rock formed of interlocking crystals ofquartz , feldspar , mica, and other minerals in lesser quantities. nuggy

 

[tamrock]

Indeed granite. "Georgia Blue" I worked for a company that sold a lot of rock drill bits to a dealer in Elberton, GA who supplied a variety of tools to the dimension stone quarries. No shortage of blue and gray granite's in Georgia. The state is famous for their stone and Stone Mountain. Stone Mountain - Wikipedia, the free encyclopedia

 

[Back-of-the-boat]

Indeed granite. "Georgia Blue" I worked for a company that sold a lot of rock drill bits to a dealer in Elberton, GA who supplied a variety of tools to the dimension stone quarries. No shortage of blue and gray granite's in Georgia. The state is famous for their stone and Stone Mountain. Stone Mountain - Wikipedia, the free encyclopedia

So the red outer core is just staining from the soils?

 

[huntsman53]

Since georgiagirl23 stated that some of the rocks have red crystals in the dark greyish inside material, I was thinking a form of Gneiss with Garnets or possibly Rubies. The outer brown shell could in fact just be good ole harden to rock Georgia clay but an acid bath might actually reveal something else entirely but what it could be, I don't have a clue.


Frank

 

[tamrock]

B of the B, I think what huntsman says about the staining is spot on, as this chunk has been exposed to the outside element for a very long time. As for what it is imo, nuggy hit the nail on the head. The red crystals, are the "other" nuggy mentions. This piece isn't as fine grain as the good quality Georgia granite and too grainy for say dimensional stone. I would say this piece came from a deeper source of the Georgia granite pluton and cooled slower, allowing the crystals to form bigger. All that said I ain't no Scott Wolter and if you notice, you never see him say that rock is a 100% this on the spot. He always says I need to do a little investigation first before his opinion is offered... Due to what I do for a living. I at times, need to come up with a opinion, when folks ask me how long will the tungsten carbide rock drill bits I sell last and how many feet can be expected to get out of one bit?. It all starts with me asking what is it we'er drilling here. I can never guarantee that figure, because the properties of rock can change in inches in some places. I just estimate what I think. Some times I'm on target and other times I'm called a BS'n salesman. I just need to understand rocks, plus I find them all fascinating and like to know more about them all.

 

[pat-tekker-cat]

Occams Razor - granite. Could it be deep slow pressurized condensed crystals and garnets? yeah maybe, east of ya, there's the amethyst and aquamarine everywhere. Are you able to get it up under a microscope or magnified for crystal structure (the ones you said got the red crystals)? Maybe some more pics......
I like rocks, too. Cool.

Oh yeah, red Ga clay.... the worst! Only way to get it out of carpet is, let it dry, then vacuum.

 

[tamrock]

Occams Razor - granite. Could it be deep slow pressurized condensed crystals and garnets? yeah maybe, east of ya, there's the amethyst and aquamarine everywhere. Are you able to get it up under a microscope or magnified for crystal structure (the ones you said got the red crystals)? Maybe some more pics......
I like rocks, too. Cool.

Oh yeah, red Ga clay.... the worst! Only way to get it out of carpet is, let it dry, then vacuum.

You could always tell folks, to wipe their feet or take off your shoes before stepping on the carpet. At my house theirs a lady that loudly says "WHY!!! CAN'T anybody wipe their feet before they come in the house" It's a mystery to me why that can't catch on