Crazy nodule, man-made, or fossil?

[icycatelf]

I found this "crazy miniature vase" in the creek gravel today and was wondering what it might be. The big thing in the middle just looks like a regular nodule to me, but the black thing hugging it looks bizarre. The black thing branches out into two hollow tubes. A magnet doesn't stick to it. The whole piece measures 4.5cm tall (black piece is about 2.5cm).

The last attachment is another one of today's finds and I was wondering if it might be Lepidodendron. I see an interlocking diamond-teardrop pattern, though it's not super distinct. I also see some small "feeding eyes," making me lean toward Stigmaria. Area shown is about 9cm long.

Edited May 15, 2016 by icycatelf

[Oxytropidoceras]

It is a natural limonite-hemitite concretion that likely is the result of the weathering of a pyrite nodule. Such concretions are often called "Indian paint pots."

Edited May 15, 2016 by Oxytropidoceras

[Missourian]

It's a trap!

[icycatelf]

It's a trap!

trap.jpg

LOL!

It is a natural limonite-hemitite concretion that likely is the result of the weathering of a pyrite nodule. Such concretions are often called "Indian paint pots."

I had a feeling it was something along those lines. Pretty interesting, though.

Edited May 16, 2016 by icycatelf

[abyssunder]

The second on could be a portion of Stigmaria of a lycopsid like Lepidodendron.

Edited May 17, 2016 by abyssunder

[icycatelf]

The second on could be a portion of Stigmaria of a lycopsid like Lepidodendron.

2012-03-09-stigmaria.jpg

I have a feeling you're right. Seems like most of the fossils I find in that area's slate are Stigmaria. I've found several (at least 7) pieces, but I've yet to find any lycopsid bark.

Question: I've seen people label the local tree-like plant fossils (Calamites, Artisia, Stigmaria) as "petrified wood," but would that term be correct? I feel that "petrified" is reserved for crystallized wood in which the rings have been preserved. I know that Calamites can be petrified in this way, but I've seen listings on eBay that define regular Calamites pith casts as petrified wood. (To my knowledge, a pith cast isn't wood at all, just sediment that filled a hollow chamber, forming a cast of the internal structure.) I think that petrified wood is always a wood fossil, but a wood fossil isn't always petrified wood.

I feel a little different about Stigmaria, however. While my pieces still aren't crystallized, I do see thin "tubes" going through the (broken) sides, making me think they're more than just casts or imprints. They also have a slightly waxy look. Would this be considered "petrified wood" or...?

I don't really mind either way, but I'm mostly checking for my mom who likes throwing the term around.

Edited May 18, 2016 by icycatelf

[abyssunder]

You are right in what you say.
Calamites, Artisia, Stigmaria are form taxa of casts of tree - like vascular plants, they are not considered trees, so I think the usage of the term "petrified wood" for these is improper. Usually the term describes a tree or tree - like plant stem/trunk which is passing through a permineralization process, when all the organic materials are replaced with minerals.