What Is This?

[americanafarm]

found this quite a few years ago while digging a pond in the backyard. It is about the size and shape of a matchbox car tire.

[MikeD]

Two segments of a crinoid stem. It was an ancient echinoderm, which lived in the sea. Looked like a flower on a stalk. They still exist today. Search this forum or google for tons of pictures and information on crinoids.

[americanafarm]

Two segments of a crinoid stem. It was an ancient echinoderm, which lived in the sea. Looked like a flower on a stalk. They still exist today. Search this forum or google for tons of pictures and information on crinoids.

Thank you very much. I've had it for about 14 or so years and never could figure it out.

[Guest N.AL.hunter]

And just so you know... Petrification is one form of fossilization.

[Mr. Edonihce]

And just so you know... Petrification is one form of fossilization.

huh?

[Coco]

OK with MikeD.

Coco

[Guest N.AL.hunter]

huh?

There are several ways something can become a fossil. Here are some: Petrification, cast/mold AKA Replacement, Amber, Frozen, Dessication/mummyfication, carbonization/distillation, and I am sure I am missing some. Most of what I find are replacement fossils.

[Mr. Edonihce]

There are several ways something can become a fossil. Here are some: Petrification, cast/mold AKA Replacement, Amber, Frozen, Dessication/mummyfication, carbonization/distillation, and I am sure I am missing some. Most of what I find are replacement fossils.

Um....yes....but I'm not sure what it has to do with this thread.

I didn't see where anyone said anything about this before you posted, and I'm wondering if you intended this to be in a different thread.

[Harry Pristis]

Um....yes....but I'm not sure what it has to do with this thread.

I didn't see where anyone said anything about this before you posted, and I'm wondering if you intended this to be in a different thread.

The title of this thread is:

What Is This? seems like it's more petrified than fossilized

'N.AL.hunter' makes a correct observation, but he doesn't go far enough.

The term "fossilized" (or some derivation) is so broadly used that it is nearly meaningless. To be a fossil is to be preserved longer than it ordinarily takes for natural forces to destroy whatever it is. Thus, you can have fossil sand dunes or fossil worm-tracks.

The term "petrified" ("turned to stone") is not a scientific term these days. You're more likely to find the term in a scarey movie than in a modern scientific publication.

The common mis-use of "fossilized" is as a substitute for "mineralized" or "permineralized." Many fossils are preserved by being impregnated or replaced by minerals, SiO2 being the common mineral.

However, not all fossils are preserved by being "fossilized" (mineralized) - European cave bear fossils are a well-known example. Cave bear bones are simply bone (that is, the crystalline structure of the original bone, minus the collagen) with no added minerals. In other words, the bone is preserved as a fossil bone, not as a "fossilized" bone.

How you use these terms will separate the newbies and curio collectors from the amateur paleo-biologists.

[Bill]

Hi All,

on occasion I've seen mold/cast and replacement, applied in different ways on this forum. Can someone please explain to me, the US meaning of each of these. In the UK, a mould/mold is the impression left by something, or for example, an article made to form the shape of a particular item, ie the wooden structure to which fibreglass is applied to make a boat, the boat being released from the mould/mold after the fibreglass has cured.

In the post above by N.Al.Hunter, he says 'cast/mold AKA Replacement'. I can see that a bivalve impression, (mould/mold), can be filled with a sediment and result in a cast of the original bivalve.

To me though, neither cast or mould/mold are replacements. I thought the term 'replacement', in the context of fossils, means the replacement of the original material by another mineral, ie, wood by silica. Not the infilling of a mould/mold, by sediment.

Edited March 2, 2011 by Bill

[Harry Pristis]

Hi All,

on occasion I've seen mold/cast and replacement, applied in different ways on this forum. Can someone please explain to me, the US meaning of each of these. In the UK, a mould/mold is the impression left by something, or for example, an article made to form the shape of a particular item, ie the wooden structure to which fibreglass is applied to make a boat, the boat being released from the mould/mold after the fibreglass has cured.

In the post above by N.Al.Hunter, he says 'cast/mold AKA Replacement'. I can see that a bivalve impression, (mould/mold), can be filled with a sediment and result in a cast of the original bivalve.

To me though, neither cast or mould/mold are replacements. I thought the term 'replacement', in the context of fossils, means the replacement of the original material by another mineral, ie, wood by silica. Not the infilling of a mould/mold, by sediment.

The words, "mold" and "cast" mean the same wherever English is spoken. You've sorted it out.

You're correct, Bill, "mold" and "cast" are mis-used from time-to-time on the forum. It's not a pervasive mis-use (like "fossilized" for "mineralized"), and I tend to ignore such an incident as a brain-cramp or as a child's error, depending on who is involved.

[Bill]

Cheers Harry, so basically it's the wrong word being used at times. We all make that mistake occasionally.

[Guest N.AL.hunter]

The term "fossilized" is perfectly legitimate: Websters below: In use since the late 1700's.

fos·sil·ize verb \ˈfä-sə-ˌlīz\

fos·sil·izedfos·sil·iz·ing

Definition of FOSSILIZE

transitive verb

1: to convert into a fossil

2: to make outmoded, rigid, or fixed

intransitive verb

: to become changed into a fossil

— fos·sil·i·za·tion \ˌfä-sə-lə-ˈzā-shən\ noun

See fossilize defined for English-language learners »

Examples of FOSSILIZE

The mud helped to preserve and fossilize the wood.

First Known Use of FOSSILIZE

1794

Browse

Next Word in the Dictionary: fossorial

Previous Word in the Dictionary: fossilise

All Words Near: fossilize

[Guest N.AL.hunter]

Hi All,

on occasion I've seen mold/cast and replacement, applied in different ways on this forum. Can someone please explain to me, the US meaning of each of these. In the UK, a mould/mold is the impression left by something, or for example, an article made to form the shape of a particular item, ie the wooden structure to which fibreglass is applied to make a boat, the boat being released from the mould/mold after the fibreglass has cured.

In the post above by N.Al.Hunter, he says 'cast/mold AKA Replacement'. I can see that a bivalve impression, (mould/mold), can be filled with a sediment and result in a cast of the original bivalve.

To me though, neither cast or mould/mold are replacements. I thought the term 'replacement', in the context of fossils, means the replacement of the original material by another mineral, ie, wood by silica. Not the infilling of a mould/mold, by sediment.

You are correct, I should not have said AKA Replacement, since that is when dissolved minerals have relaced the organism, usually calcite or silica. Casts can be external casts or internal casts.

[tracer]

one of the most knowledgeable people i ever knew with regard to the english language said that dictionaries chronicle the language - they do not establish it. language is ever-changing, and its main purpose is communication, so it is a subversion of its purpose to use it for establishing social status, etc.

at any rate, i think that the term "replacement" can be used very broadly, and so people kinda need to use more precise language when they wish to more precisely present a concept. i also think the terms "mold" and "cast" have resulted in some degree of confusion for the perfectly acceptable reason that they have become to some extent interchangeable in usage. normally, a mold is an external impression made of something. a cast can then be made of the mold to create a likeness of the original thing. but it isn't that simple. say you have an original bivalve shell buried, and it fills internally with lime-mud and hardens. some might assert that is a cast. i would assert that it's ok if you call it that, but i consider it an internal mold, in that it is an impression of the original shell - just an internal one. ok, so now the lime-mud on the outside of the shell hardens. i consider that an external mold. ok, now the shell dissolves and what's left are the inner and outer molds. the inner mold is a "steinkern" - sure why not? ok, now by whatever process, silicaceousness gets into the molds and hardens harder than hard. now you have a cast of the original shell, sandwiched (no, i'm not going to get off onto what a sandwich is) between the internal and external molds. now some lime-mud eating bacteria come along (i just made those up) and eats the internal mold. but nature abhors a vacuum (specially a hoover [just kiddink, herbie]), so along comes some lithoshale and fills the void. so now i guess you have a cast of a cast of a mold. or do you have a mold of a cast of a mold? don't know, do you? right. neither does anyone else, because the terms are mere human constructs for whatever humans wish them to mean, so you can decide too, assuming you're not a bot, like me.

a steinkern can be considered a cast or a mold, depending on whether the original shell was present when it was formed, or a cast of the shell, but also depending on whether that matters enough to you to reserve the term cast to applying exclusively to something formed in a mold and the term mold to applying exclusively to an impression formed from an original object.

but forget about molds and casts and remember this lesson. whoever gets to define the terms wins; always. so don't let anyone define your terms for you. and don't let yourself get cast too narrowly into anybody else's mold.

[Mr. Edonihce]

The title of this thread is:

What Is This? seems like it's more petrified than fossilized

Doh!

Sorry....completely missed that.

[Harry Pristis]

The term "fossilized" is perfectly legitimate: Websters below: ....

You seem to have missed the point, NALh, which is:

The term "fossilized" (or some derivation) is so broadly used that it is nearly meaningless.

It is near meaningless in the context in which we are operating on The Fossil Forum. A subscriber here may write, "the bone is fossilized" when he may be trying to tell us that "the bone is mineralized." In such a post, "fossilized" is not incorrect in the dictionary sense; but, the term conveys little or no information to the readers here.

[americanafarm]

geez, sorry for the misuse of the word in my original post.

[tracer]

geez, sorry for the misuse of the word in my original post.

you didn't misuse any words. and i do hope you go look around and find some more fossils in your area and post pictures of them.

[Auspex]

geez, sorry for the misuse of the word in my original post.

You have a ring-side seat to what happens when scientists (and the seriously scientific minded) "chew the fat" . Nomenclature, in the quest for concise communication of complex ideas, becomes sacrosanct. Please, please don't take any of this as a criticism of how you asked for help!

[piranha]

You have a ring-side seat to what happens when scientists (and the seriously scientific minded) "chew the fat" . Nomenclature, in the quest for concise communication of complex ideas, becomes sacrosanct. Please, please don't take any of this as a criticism of how you asked for help!

Thanks for that Chas ... well said and a big TFF Welcome is extended to Americanafarm.

The only bad question is the one you don't bother to ask. We are all so glad you are here !!

[Mr. Edonihce]

geez, sorry for the misuse of the word in my original post.

you didn't misuse any words. and i do hope you go look around and find some more fossils in your area and post pictures of them.

You have a ring-side seat to what happens when scientists (and the seriously scientific minded) "chew the fat" . Nomenclature, in the quest for concise communication of complex ideas, becomes sacrosanct. Please, please don't take any of this as a criticism of how you asked for help!

Thanks for that Chas ... well said and a big TFF Welcome is extended to Americanafarm.

The only bad question is the one you don't bother to ask. We are all so glad you are here !!

I agree.

The discussion that ensued after your original post really has nothing to do with you or your original post.

Instead, it's just us taking off on a tangent, that, although was related to what you typed, that fact was just another excuse for us to converse with each other about something we have interest in.

It happens from time to time, and that's just part of life with us humans

Maybe I'm way off there, but that's the way I see it.

Thanks for sharing, and keep it up.

[Tessy]

You have a ring-side seat to what happens when scientists (and the seriously scientific minded) "chew the fat" . Nomenclature, in the quest for concise communication of complex ideas, becomes sacrosanct. Please, please don't take any of this as a criticism of how you asked for help!

+100

You should feel proud you got all the regulars in a debate! IMO

As somewhat of a newbie I've found that this is a sign of a great pic/post. What you don't want is a "too blurry" or 0-1 replies...that's happened to me.

Your pic #1 looked to me, at fist glance, like two checker piece glued together!

Everyones very generous I found.

Edited March 3, 2011 by Eli

[Bill]

geez, sorry for the misuse of the word in my original post.

No offence meant and no need to be sorry.

On my part it was primarily a question about N.AL.Hunter's post, 'cast/mold AKA replacement'.

The use of cast/mold have been interchangeable on here, I was just seeking clarification.

Please carry on posting your finds, I know we will all enjoy seeing them.

Edited March 3, 2011 by Bill

[Guest N.AL.hunter]

You seem to have missed the point, NALh, which is:

The term "fossilized" (or some derivation) is so broadly used that it is nearly meaningless.

It is near meaningless in the context in which we are operating on The Fossil Forum. A subscriber here may write, "the bone is fossilized" when he may be trying to tell us that "the bone is mineralized." In such a post, "fossilized" is not incorrect in the dictionary sense; but, the term conveys little or no information to the readers here.

What I am disagreeing with is this statement "The common mis-use of "fossilized" is as a substitute for "mineralized" or "permineralized." Many fossils are preserved by being impregnated or replaced by minerals, SiO2 being the common mineral."

It is perfectly legit to substitute the word "Fossilized" for any and all types of fossils. It is the broadest term that covers "mineralization" or "permineralization" or "dessication" or whatever. It all depends on the authors intention and audience. No where in the definition of the term does it refer only to organisms that have been "turned to stone". Therefore, the term covers those fossils that have been "turned to stone" and those that are still original material. If the author wants to convey more precision, then they can do so with the term that better describes the type of fossilization the specimen has undergone. However, this being an amateur forum (and I am nothing but an amateur), we must expect many members to use the broadest terminology.