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Questions tagged [identification-request]

For help in identifying objects such as rocks, minerals, clouds, etc. Please include as many details as possible.

2
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1answer
218 views

stalagmite Identification and formation process needed

I can not find a similar image or info on the net to identify my presumably Cave stalagmite. I would like to know where and how it formed. Now the black interfiling i'm assuming to be water that ...
3
votes
1answer
187 views

Unusual rock identification needed

This was found near a river on sand with the green side down. The first picture of the rock has a glossy finish. The second image has a high green color that resembles a crust layer involving heat of ...
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vote
2answers
485 views

How are natural specimens, such as ‘Moqui Marbles’, distinguished from man-made artifacts?

If a particular type of rock specimen is found throughout Earth and is made entirely of natural minerals, but the individual specimens differ minutely from another in size and shape and look to be ...
3
votes
2answers
345 views

Growth identification on obsidian needed

What are the small white growths on my obsidian? And does this specimen look odd or rare?
3
votes
2answers
196 views

Can anyone identify and describe this rock?

Can anyone help me identifying this rock and describing it? Saw this today while driving.
2
votes
2answers
95 views

Describing this rock

Is this rock granite? Can anyone help me identifying this rock and describing it?
4
votes
1answer
64 views

What type of cloud is this?

I live in a sub-tropical region of Australia. Earlier today, we experienced temperatures of 31C and it was clear about 2 hours before I went out and noticed the following clouds directly above my ...
6
votes
1answer
699 views

Rock identification: meteorite or lava?

I was told by a crystal quartz store owner it was a type of lava rock but I have high doubts. hardness: diamond size: 4'' $\times$ 4'' weight: 1.5 lb location: unknown smell: sulfur trait: ...
3
votes
2answers
565 views

Rock identification: opal or crystal?

I picked this up from a good friend, he didn't have any information but someone said it was an opal and not a crystal. It is see-through like foggy glass in some spots. hardness rated as quarts size ...
5
votes
3answers
647 views

Rock or possible fossil identification needed

Found in Cressy River, Stanislaus County, California in April 2014. The rock is 3" $\times$ 1" weight is 7 oz and from 1-10 on hardness i give it a 8 . I found it in the river. It caught my eye ...
2
votes
1answer
38 views

Why does the color of this hillside rock vary?

Below is a roadcut in central Marin County, California, in an area maps show to have Franciscan melange. I assume this is graywacke, but as you can see it varies from gray on the sides to a buff ...
6
votes
2answers
196 views

Rock identification and features

The rock is approximately 12cm in length and from what I can tell this is a sedimentary rock and is a conglomerate. I'd say it was from a high energy environment due to the round gravels. This is all ...
8
votes
2answers
656 views

Rock ID: Large, heterogeneous, magnetic rock in Cascade Range, Washington, USA

I found this rock in a glacial till in north central Washington State, on the east side of the Cascade Range. The dark round crystals are roughly 1 inch (2.54 cm) by 2 inch (5.08 cm) in size. The ...
6
votes
1answer
346 views

Is this iron ore?

Is this iron ore? I found it in the back yard in Western Australia few years back; it has a roughish surface. It was sticking out of my grass. It has sand grains stuck on it. It is reasonably hard, ...
8
votes
1answer
2k views

What is this blue rock?

I am trying to identify a rock my husband found.The rock was found in Columbus Ohio about 20 feet (6 m) down. It is about the size of a basketball and extremely heavy (90 lbs) and difficult to cut ...
5
votes
1answer
155 views

Identification - is this granite?

What type of rock is this? It's sold as poultry grit and says granite on the bag, but I want to be sure. Canadian Quarter (Ø = 23.88 mm) shown for scale.
4
votes
1answer
420 views

Fossil or Beef Limestone?

I found the below sample on Monmouth Beach near Lyme Regis and I am unsure if it is a fossil or simply beef limestone. The beef limestone is from fibrous calcite layers within a shale (known as shales ...
11
votes
4answers
2k views

What sort of rock is the large polished boulder?

This large polished boulder sits outside one entrance the University College Hospital in London: Here is a close up: What sort of rock is it and how would it have formed?
8
votes
2answers
647 views

What type of rock is this paving stone and what is the origin of the red colouration?

This paving slab is part of the floor of the new atrium in Kings Cross Station in London: The paving slabs are mostly grey but some contain areas of this reddish colouration. They are all fine ...
8
votes
1answer
589 views

We found this rock and we don't know what it is

I found these rocks at a road in Sweden. They are different from the other rocks used for the road. The hardness is higher than 5.5 as the rocks aren't affected by a knife. the size is 2.0-2.5cm ...
6
votes
1answer
501 views

What kind of rock is this (from UK)?

What kind of rock is this? It was found in Threemilestone, near Truro in Cornwall, UK. The rock has a hardness of over 5.5, as a knife doesn't scratch most parts of it. It is 10cm across the top, ...
4
votes
1answer
202 views

What type of gem is this?

I was wondering what type of stone this is. I tested it on Mohs hardness scale. It scratched quartz. I found it at Crystal Cave in Kutztown, Pennsylvania. They were selling bags of gems you could sift ...
5
votes
1answer
442 views

Icelandic rock I am trying to identify

This is a rock that I picked up from underneath a melted segment of Glacier in east Iceland. It is not unusually heavy or light for it's size. I can scratch the surface away with a penny. The ...
5
votes
1answer
757 views

What type of sparking stone could this be?

A few years ago, I went to a beach in the south part of Chile, specifically Lake Lanalhue, it was filled with special rocks that when you picked one up and threw it against another that you would see ...
13
votes
2answers
785 views

What are these lake-like blue patches in the desert, visible in satellite image?

I found some blue patches in the Arabian desert in Google Earth. It looks like as if they were lakes with sand dunes rising out of the water. But there isn't water in the desert, at least not this ...
6
votes
1answer
261 views

What type of storm cloud is this?

We have had (and are still experiencing) waves of storms passing through this area of the central Queensland 'Capricornia' coast, Australia. This area is a subtropical coastal environment, close to ...
5
votes
1answer
227 views

What are these tumbled colored rocks?

I've been sent these rocks by a friend, but I am truly awful at identifying them because they aren't my field at all. I know some of them, but I was wondering if you could classify them all for me so ...
13
votes
1answer
655 views

What type of cloud formation are these dark low-hanging clouds?

I was thinking it could have been a non-rotating wall cloud, but I'm not sure. YouTube video Picture taken on September 9 2014... between 5-7 pm in North Georgia, about 40 miles north of Atlanta.
10
votes
1answer
720 views

What kind of coal did I find?

I found a piece of (what I believe is) coal, on Cape Cod last week. Its density is 1.43 grams per milliliter. With this information is it possible to know whether it's Anthracite, Bituminous or ...
8
votes
1answer
746 views

What is this Cape Breton rock?

What is this rock? I found it in Cape Breton, Canada
5
votes
1answer
157 views

What is the name of these crystals?

I tried searching for matching crystals online, my guess is Bournonite. What crystals are these? This image was taken by a relative at some sort of museum. The image and the observation that they ...
8
votes
1answer
1k views

What is this brown and white rock?

We found this rock in our backyard. Could someone please tell me what it could be?
5
votes
5answers
1k views

What type of rock is this that is light colored with greenish crystals?

I found this rock. It is probably a very common rock but could an expert please tell me what rock this is?