How do I make good fossil impressions?

[gobbler716]

I found  some fossils on private property that I may not remove.  What materials can I use to make some impressions?  I make plaster casts of animal foot prints all the time, but this is different.

These are ones for which I have photos, but there are a zillion more in this area....some of these are probably not fossils.

[Miocene_Mason]

I have never done anything like this, but I imagine a  silicon mold may work, although it would be time intensive.

[FossilDudeCO]

I wonder if you could push clay on to it, let the clay harden (or help harden it) and then make your silicone mould.

[ynot]

I do not see any fossils in those rocks.

If You put anything into the crevices on them it will have a hard time coming out.

Your best bet would be a pliable (when dry) silicone.

Not sure but I think there is a product that is made for that.

[RJB]

I dont see any fossils either?

 

RB

[gobbler716]

These are ones for which I have photos, but there are a zillion more in this area....some of these are probably not fossils.

[erose]

Good photography may be the better choice. Put something in for scale like a coin or small ruler.

 

Silicon molds are best because once cured you can pry them out of the nooks and crannies. You can find tons of info online.

 

[Ptychodus04]

I use Equinox silicone putty. It is a 2 part that you mix 1:1 by volume. It sets in a couple minutes. You press it into/onto whatever you wat to make a mold of and peel it off when set.

 

You can add onto parts that are in place a bit at a time in order to mold large fossils such as dinosaur tracks. This let's you mix smaller batches since the working time is short.

 

I mostly use it for making molds in order to cast replica parts for restorations. It provides great detail and is self supporting but is rather expensive.

[gobbler716]

Thank you so much.  I used some 100% silicone and really messed up.  It will not peel off of my fossil.  Thank goodness I used a fossil that I have many similar ones....

[Ptychodus04]

2 hours ago, gobbler716 said:

Thank you so much.  I used some 100% silicone and really messed up.  It will not peel off of my fossil.  Thank goodness I used a fossil that I have many similar ones....

 

Products like silicone caulk, etc. are designed to stick to surfaces in order to seal them. If you use a product like that you have to first apply a release agent so it won't bond to the fossil.

 

The Equinox product does not require the use of a release agent.

[gobbler716]

I REALLY appreciate that!!!!!

[gobbler716]

I found Equinox at Amazon.....thanks again!

[Ptychodus04]

4 hours ago, gobbler716 said:

I found Equinox at Amazon.....thanks again!

 

You're very welcome. There's a fine line between too thin where it tears and too thick where it's not flexible enough. Once you find that happy spot, you can make several casts from one mold.