Austin Chalk/ Trinity River North Texas Fossil cleaning

I have been finding some really cool fossils in Austin Chalk outcroppings around the Fort Worth, Tx area.

I have not treid to "free" one of the fossils from it's surronding/encasing chalk (matrix?) material.
I read about vinegar... but to me the chemical make-up of these specimens is likeley very homogenous across the specimens entire structure including it's surronding/encasing chalk material.

Any ideas?

Thanks in advance.

Hi Hank and welcome. I live in Austin and deal with the same stuff you are talking about. Wise move not to use the vinegar. The chalk is composed of app. 95% lime. This same lime many times will replace the minerals composing the creature originally. Shells can be freed many times by soaking the chalk in water. It is easy to break up when wet. If it is a fragile fossil you may want to stabilize it first by making a thin mix of Elmers glue and water and brushing it on in 3 coats or so. Just enough to where a slight sheen appears and then stop unless you like the glossy look. If thats the case add more mix. A handy tool also is the small electric vibrating engraving tool. It acts like a mini jackhammer and has settings to regulate speed. Hope this helps.

I will get a "dremel" tool, along with my circular lighted magnifying glass... see if I can work it out. I didn't think chemicals was going to be the answer.

Thanks for your input.

Hank

A Dremel is very handy. Mine sees a lot of use on rocks. I use a diamond blade on mine to cut rock but they wear out pretty quick with harder rocks. Also a Dremel is a rotary tool where the engravers are basically a reciprocating tool that moves up and down instead of round & round. It is a whole different action.