Fossil

Here's a fossil I found on a beach in southern England last month. It's just a bit bigger than my thumb! c&c welcome

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Thats amazing!have you had the material looked into, it looks like the shell material has been completely replaced with pyrite!

no i havent but it is from the jurassic coastline. I brushed it gently in cold water and removed the clay which then revealed the golden look. It gets a bit addictive once you find something like this, you can spend hours searching along the coast .

Kraig C wrote in post #2380297
Thats amazing!have you had the material looked into, it looks like the shell material has been completely replaced with pyrite!

Looks like small ammonites. We get pyritized fossils around here occasionally. They do have that brassy look of pyrite. Interesting subject.

Great shot- amazing fossil
Brian V.

Ammonites and other invertebrates are the most common fossil replaced with Pyrite, in this form it's referred to as Marcasite, due to the lower temperature that it replaces the host.

is that similar to fools gold?

alexf wrote in post #2380436
is that similar to fools gold?

same mineral

ok thanks. I also found this, any ideas?

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So, from a mineral collector's notes about this material in fossil replacement etc, "it quickly degraded into an oxide and releases a sulfuric acid gas that attacks papers and boxes that contain specimens so, to prevent ruining other specimines, containers and lables, keep it in sealed in archival quality plastic container. When opening large specimines of marcasite for handling, open them a well ventilated area to avoid succoming to sulfur dioxide gases that may have built up over time. Another thing people have suggested is there may be an anearobic reaction taking place by ancient bacteria, they suggest to preserve the mineral, steralize it with lysol about as often as you dust off your other specimines to reduce the amount of deterioration.

wow thanks. I have read somewhere that I caould also coat it with PVA glue ( a type of sealant used on walls etc). Do you know what thw amber coloured crystal type stone above is? That measures approx 6 inches across

hard to tell, some small crystals form in blankets between fissures in rocks, it's could be a calcite mineral.

i can see formations in cracks in the rock, not sure if this bigger piece helps more?

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Awesome, love the first one.

We were just there in June.. but the fossils we found weren't nearly as cool as that.

ammonites, right? gorgeous!