Assistance with a rock identification 2 (southwest part of the U.S.)

In summary: I've been to the Grand Canyon, Monument Valley, and many other iconic sites around the Southwest. Basalt is a common rock type in that region.Basalt is common in the southwest US, so your guess is as good as mine as to where this might be from. There are plenty of basalt outcrops around that area.
  • #1
C Mac
6
2
Hello,
Could I please get assistance with a rock identification. I came across this one in the southwest part of the U.S. While I see a lot of slag from old mines, this rock appears to be something different than slag. Besides, it was the only dark colored rock I came across that day. It also appears to have grooves of some kind.

This is my second post asking for assistance with a rock identification, so just a reminder, I do historical research and at times, come across (what I consider) odd rocks that don't match anything else in the area.

Please see the attached photos and let me know your thoughts or if you have additional questions.
Thank you in advance.

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  • #2
Just a first-pass guess, details left for the more knowledgeable ones here. Is it magnetic, heavier than expected? Could me a meteorite.
 
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  • #3
C Mac said:
I came across this one in the southwest part of the U.S.
Specifically ? ... state and area in state ?My initial thoughts would be Basalt
There's a lot of volcanics in Arizona and a reasonable amount in New Mexico
I would have to dig through my travel pix, but did take some good photos of lava flows in NM

Dave
 
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  • #4
Thanks for the feedback Tom and Dave,
No, not magnetic. Also, doesn't seem heavier than expected. Actually, it might seem a pinch lighter than expected, but it doesn't have any identifiable voids to air pocket - that I can see.

I believe this was also SE Arizona. Please understand that unless I take a photo at the time I come across a rock, I probably won't have specific information since I'm not out actually hunting rocks.

Now that you say, basalt, I remember seeing a topo map identifying a "cinder hill" about 40 miles SE of where I picked this up, so maybe I came across this rock after it had been previously moved? There were just no other rocks like this in the area, but it would make sense it might be basalt.
 
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  • #5
C Mac said:
No, not magnetic. Also, doesn't seem heavier than expected. Actually, it might seem a pinch lighter than expected, but it doesn't have any identifiable voids to air pocket - that I can see.

OK :)
Being magnetic doesn't confirm a meteorite. Other tests would have to be done for that. Even basalt can show magnetic tendencies
as it often has a reasonable around 20 - 40% iron content.

C Mac said:
I believe this was also SE Arizona. Please understand that unless I take a photo at the time I come across a rock, I probably won't have specific information since I'm not out actually hunting rocks.

that's OK, no problems :smile: ... state and area in state is a great start. As you could imagine, geology can change rapidly across a given region.
So the more accurate you are, the easier it makes to identify :smile:
C Mac said:
Now that you say, basalt, I remember seeing a topo map identifying a "cinder hill" about 40 miles SE of where I picked this up, so maybe I came across this rock after it had been previously moved? There were just no other rocks like this in the area, but it would make it might be basalt.

that really helps narrow it down
Cinder Hills is just NE of Flagstaff. Been there a couple of times. that whole region from the Flagstaff area and right
up to the Grand Canyon is full of volcanics

awesome stuff ... I look forward to seeing your next queryDave
 
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  • #6
Sorry, let me provide a little clarity. I was SE of Tucson in SE Arizona when I came across this rock. SE of my location where I found this rock, close to the Arizona, New Mexico, Mexico border, is a small hill identified as "cinder hill." My bad if I made this confusing, but there is a hill in the area of Arizona, New Mexico, and the Mexican border identified as "cinder hill.." Anyway, same name as the one up in Flagstaff, but geographically in a different part of the state.
 
  • #7
C Mac said:
I was SE of Tucson in SE Arizona when I came across this rock. SE of my location where I found this rock, close to the Arizona, New Mexico, Mexico border, is a small hill identified as "cinder hill." My bad if I made this confusing, but there is a hill in the area of Arizona, New Mexico, and the Mexican border identified as "cinder hill.."
No Problems :smile:
I haven't been as far south as Tucson. Always wanted to get to Tombstone, AZ., just for the historical value, maybe one day. :biggrin:

Anyway, still plenty of volcanic outcrops around that SE area of the state, so I would expect that you would find plenty of evidence
scattered around the areaD
 
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Related to Assistance with a rock identification 2 (southwest part of the U.S.)

1. How can I identify a rock found in the southwest part of the U.S.?

The best way to identify a rock from the southwest part of the U.S. is to first observe its physical characteristics such as color, texture, and shape. Then, you can use a field guide or online resources specific to the region to narrow down your options and make a more accurate identification.

2. What are some common types of rocks found in the southwest part of the U.S.?

Some common types of rocks found in the southwest part of the U.S. include sandstone, limestone, shale, volcanic rocks such as basalt and obsidian, and sedimentary rocks like conglomerate and breccia.

3. What tools do I need to identify a rock from the southwest part of the U.S.?

Some useful tools for identifying rocks in the southwest part of the U.S. include a hand lens for examining small details, a streak plate for testing the color of a rock's powder, and a magnet for determining if the rock contains iron.

4. Are there any specific features or characteristics to look for when identifying rocks in the southwest part of the U.S.?

Yes, there are certain features and characteristics that can help identify rocks in the southwest part of the U.S. For example, sedimentary rocks may have distinct layers or fossils, while volcanic rocks may have a glassy appearance or contain air bubbles. It is also important to consider the location and geology of where the rock was found.

5. Can I use a smartphone app to help identify rocks in the southwest part of the U.S.?

Yes, there are several smartphone apps available that can help identify rocks in the southwest part of the U.S. These apps use image recognition technology and provide information on the rock's characteristics, formation, and location. However, it is always recommended to double-check the identification with a physical field guide or expert.

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