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Doug Von Gausig

This dolomite stone was discovered near Chasm Creek, central Arizona. It appears to have the fossilized impressions of raindrops splashing into a fine muddy surface. The stone seems to be dolomitic, as HCl causes a low fizz, unlike typical limestone's more energetic fizzing. Most of the "splashes" have the central "rebound" splash seen in my high-speed imagery of water droplets. That central rebound appears to have been broken off over time. 

 

Does my assumption that this is a somehow frozen-in-time rain shower make sense?

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Raindrops-040521-5D Mark II-IMG_0128-1m.jpg

Raindrops-040521-5D Mark II-IMG_0129-1m.jpg

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DPS Ammonite

Are the “raindrop” impressions silicified? I am thinking that they are something other than raindrop impressions since the carbonate was most likely deposited underwater. 
 

There are lots of similar looking silicified structures in Mississippian carbonates in central AZ. 

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Doug Von Gausig
37 minutes ago, DPS Ammonite said:

Are the “raindrop” impressions silicified? I am thinking that they are something other than raindrop impressions since the carbonate was most likely deposited underwater. 
 

There are lots of similar looking silicified structures in Mississippian carbonates in central AZ. 

They do appear to be silicified -- they don't effervesce in HCl, but the substrate does. These should be Devonian. They were with lots of Devonian dolomite.

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DPS Ammonite

These also could be poorly preserved corals, bryozoans or sponges. Dissolve some out to see if it looks like they were attached to something on one side.

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raindrop impressions tend to be simple circular dents, craters.  I have seen them in Jurassic & Paleozoic rocks as well as on dried mud in the Sahara.  And I agree with DPS that the rock seems to be  limestone, so formed underwater and away from any possible raindrop damage.  

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Myrmica

I agree that this may have been something like a sponge but unlikely to be be raindrops because of the reasons given above.  I wonder if some original organic material provided the nucleus for deposition of harder minerals that were then left as the apparent rims of the rain 'drops'?

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PaleoNoel

I agree w/the others, not raindrops, as the little indentations tend to be more numerous. Yours appear to be a series of small iron bearing concretions.

Example from Wikipedia below

Raindrop impressions - Wikipedia

Edited by PaleoNoel
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