What makes Merrit Island Microsfossils attracted to a magnet?

[IonRocks]

I have just noticed that many of the larger microfossils I have found are noticeably attracted to a strong neodymium magnet.

What has occurred in fossilization for this to happen?

[Kane]

My guess would be the presence of iron oxide, which has more magnetic quality than pyrite (iron sulphide). In anoxic sea-floor conditions, the process of decomposition may involve higher amounts of iron oxide compounds, which under the right conditions can lead to pyritization - but not always! Essentially, the preservation of these fossils most likely occurred in marine conditions where the sea floor was rich in iron oxide compounds.

[doushantuo]

which large microfossils?

Agglutinatiing forams?

[IonRocks]

I have found a variety of them to be attracted to a magnet, including jaws, large bones, and teeth.

in the shells/sand there are also black rocks (material similar to the fossils) which almost all show attraction to the magnet.

 

ive just noticed the larger ones seem to be more so attracted than the small ones (which I guess is kind of odd, the smaller ones being lighter and such, but I don't know enough about magnetism)

[Bag of bones]

Chiton teeth have megnatite in them. Making them magnetic.  Not sure about your fossils? Interesting.  

[doushantuo]

Might be caused by iron redeposition of detrital minerals and diagenesis.

Depends if the diagenesis was early or late,the kind of sulfate reduction(anaerobic or not),magnetite stability,type of bacterial community,and mineralogical parameters

 

 

[doushantuo]

Ther are beasties called magnetofossils,BTW

[Bag of bones]

I have lots to learn. You must have a PhD? You are talking to a dumb dumb I was recently reading about magnatite naturally occurring in organisms. Chiton teeth, bacteria, possibly in Humans.  Not that this has anything to do with his fossils.  Just wondered if it's megnatite that is making his fossils megnetic? 

[IonRocks]

Not an amazing picture, but might help a bit.

essentially all fossils in this picture are weakly attracted to a magnet. 

On the left are fossils that are more strongly attracted to the magnet. At the top are some flatter fossils that I could stick to the magnet while upside down.

 

also shows the magnet I used, too three fossils attached to it.