What are these?

[rock]

I found these today and dont know what type they are. We have black chert here but this doesnt look like the chert I find. This is one piece from different directions.

 

[rock]

This is the other one

 

[StoneWhisper]

A common stone with an uncommon attachment.. obsidian maybe?.. (black tar looking substance)

 

[Eu_citzen]

Try a hardness test.

 

[rock]

Ok it feels slick where it is broken. Sounds like glass when you tap it. There is no buildings out there but they do plant crops so maybe something from the tractor.
We dont have obsidian but you never know. It doent feel heavy like chert. What type of hardness test can I try? I have never done one before.

 

[rock]

Someone said it might be a type of slag glass. So it probably is, thanks for your help.

 

[Eu_citzen]

Doesn't look like your typical slag IMO. Hardness test - also try a streak test.

 

[rock]

Doesn't look like your typical slag IMO. Hardness test - also try a streak test.

Yeah I didnt think slag but wasnt sure. How do you do the hardness test?

 

[Eu_citzen]

You take something of a known hardness and try to scatch the unknown thing.
A normal knife will be somewhere in the 5-5.5, quartz is a 7 etc etc. Search for "Moh's hardness scale".

 

[rock]

OK i just tried to scratch it with a knife it didnt scratch, I used a piece of quartz a lite scratch but not much. I really had to bare down on it to get that. I tried a old tile by rubbing it and it scratched the tile and didnt leave a color mark. I have no clue

 

[Brian T. Booth]

The first set photos the sample looks like slag to me. I don't believe it's obsidian. On the second set of photos the sample is confusing. It could be a rock that was infused with the slag. Or it almost looks like a rock that got some kind of asphaltic substance on it maybe. You said you found it in northern Georgia. Where did you find the samples? In a creek? Along a creek? In the woods? Was there an old mine near where the samples were collected? Did you dig it up or was it on the ground? Any old roads in the area? These questions can give me a better idea of what it might be. They are very interesting samples. I will think about and observe the samples more. Love a challenge.

Thank You,

Brian T. Booth

 

[rock]

I found it in a field where they plant crops. No paved roads it is very open. I have found some old red bricks scattered as in one here one way far away. None in that spot but there could of been some type of old building out there yrs ago. I have found some older glazed pottery pieces around that spot. One person said possibly a Black Smiths residue. But I dont know much about Historic relics. Thanks for checking it out for me.

 

[Brian T. Booth]

Rock,

After observing the photos more I don't think it's a natural occurring rock/mineral. I might be wrong. I can't say definitely on what it is. Sorry I couldn't be more informative. If you have any more questions don't hesitate to ask.

Thank You,

Brian T. Booth

 

[rock]

Thank you for looking. It was the only one out there like it and I did notice it has sand stuck to it so it was probably liquid at one time. There is no other outer cortex like normal rocks.