creme filled agate?

[gpanick]

New rockhound here. Hope the pictures are here too. Found this in a 'gem bucket' yeah I know, anyway, what in heck is it? Bone with marrow? It sure looks like an agate on the outside, has all the features of one.
The overall length is about 3 1/2", the filling size is 1 x 3/4". No obvious crystals inside, looks like wet sand, but is solid.
Will wait to see if pics transferred, write more if necessary.

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[QuarterMaster]

Looks like calcite or dolomite. Geodes, Rocks and Minerals, Kentucky Geological Survey

[Bajahunter]

Do any of those pieces fit together?
My first thoughts are it's a fossilized bone.

[Eu_citzen]

My first thought it some kind of chalcedony.

[Bajahunter]

from the web site
Mineralized fossil bone

Implications

From these specimens, the following observations can be made:

1. Bone mineralization textures are very distinct from most other types of mineralization, because they concentrically infill tubular cavities (Haversian canals). This would preserve indication of the former presence of the canals, even if surrounding material were completely replaced, with none of the structure of the bone itself preserved.
2. The textures of the typical minerals involved (calcite and quartz) are drastically different from that observed in clastic sedimentary rocks like sandstone in thin section. even if similar minerals (e.g., quartz) are major components.
3. In general, it is not possible to confuse the infilling of Haversian canals with other types of structure, except perhaps other types of fossils that also produce tubular cavities at this scale (e.g., the vascular systems of plants -- e.g., permineralized or petrified wood), because the infilling of former cavities is so distinctive.
4. Haversian canals must be infilled prior to replacement of fossil bone in order for the canals to be preserved. (This is common sense, but it seemed worth mentioning anyway :-))

Another link to a list of fossil sites in SC.
South Carolina Fossil Sites and Collecting Localities
Did you ask for an opinion from the people that sold you the gem bucket?
Are you close to any universities? Send the pics to the geology dept. and see if you get a response.

[gpanick]

Yes, it was one piece, thought it was agate so broke it open.

[Bajahunter]

If it is agate (Chalcedony) then it should should have a concoidal fracture on the edge and have a hardness of around 7.
A bone can be replaced with chalcedony or other minerals like calcite, as it is mineralized.
The reason I keep coming back to bone is the fact that it looks like it has some of the same kinds of internal structures that a bone would have.