Unknown Glossy patch

[0lderthandirt]

Arizona, Mississippian, Redwall limestone,  Mooney member. 

 

Hello,  hope everyone had a good Christmas.  About a week ago I found the first one of these two. Flipped the rock over and the small glossy area really stood out. First one I've seen. Then today I found another, about the same size,  roughly 3/8". I have no idea what this could be,  any thoughts would be appreciated. 

@Arizona Chris  have you run across this? 

[Ludwigia]

The photo is too out of focus to make out any details. Can you please try to sharpen it up a bit?

[0lderthandirt]

Hopefully these are clearer. Hard to get cellphone to focus on it. 

[0lderthandirt]

This is using a magnifier app. It appears very rough but I think it's smooth and glossy. 

[Innocentx]

Have you taken a brush to this yet?

[0lderthandirt]

No I hadn't until just now and it made no difference. They are both very clean, I think because they are smooth as glass. 

Lol.. ok.. as I was feeling it with my fingertip, I pushed my fingernail into it and it wasn't hard like rock. So I pushed a small screwdriver tip against it and it has some movement. It's got to be something to do with some freak Arizona bug, eggs or larva or alien bug fetus. Both rocks are outside now and my skin is still crawling. I'm just glad whatever it is it didn't chew its way out and is crawling around my house.

[KimTexan]

Interesting. I’ve never seen an egg/larva case like that. Good to know in advance.

[Archie]

Hard to say for sure from photos but this appears to be the silk cocoon of a spider, which are often found on the underside of rocks.

[0lderthandirt]

4 minutes ago, Archie said:

Hard to say for sure from photos but this appears to be the silk cocoon of a spider, which are often found on the underside of rocks.

There are many of those, in fact I have several from just yesterday but those are usually white and silky, easily tear apart with a stick. This is like a stiff leather, kinda flexible but tough, and of course this weird brown color. I've seen the little dry hard mud things that have the wasp larva and paralyzed spiders (creeps me out) and amber pods of praying mantis, cocoons. .. but this is new to me. I truly thought this was part of a crinoid when I brought it home, feeling it with a fingertip it felt like polished rock and both rocks have crinoids. 

[Fossildude19]

Could it be something like a lichen, or fungus?

[Rockwood]

50 minutes ago, Fossildude19 said:

Could it be something like a lichen, or fungus?

Doubtful. Lichens usually stand proud, and fungus would need something tastier than rock to eat.

I'm thinkin' anyway.

[The Amateur Collecter]

Maybe it's just my eyes straining at the picture, but where they are located it almost looks like there are indents in the rock? Or do they stick out/off the rock a little bit?

[Arizona Chris]

Preservation is poor, however It almost looks like a blastoid tegmen, perhaps Orophocrinus that is coated by a silica mineralization.  They are very common in the Mooney falls member.

[0lderthandirt]

4 hours ago, Arizona Chris said:

Preservation is poor, however It almost looks like a blastoid tegmen, perhaps Orophocrinus that is coated by a silica mineralization.  They are very common in the Mooney falls member.

That was my original thought when I turned over the first rock. These are not fossils though because it turns out they are flexible. I should peel one off the rock and see what's actually behind it but I just hate bugs. I did just double check and here is a picture showing it deflecting from a screwdriver tip.