When Does A Fossil Need Further Preperation?

[dragonzrmetal]

Of course, removing matrix can improve the aesthetics of a fossil, but when is preperation such as use of chemicals I have heard of important for preserving a fossil's structural integrity?

I've noticed cracking in this trilobite, as can be seen in the picture. I procured this fossil when I was about ten digging in the shale at Charmouth, which my father never admitted to planting there when I wasn't looking. Is cracking normal in a fossil like this? It must have come from a fossil shop, but it doesn't look like it's been prepared like other trilobites do. My real question is, has this fossil been prepared?

I have lots of ammonites and a couple Gryphaea that do need preperation, and are still embedded/surrounded in a lot of matrix. All I've ever done to them is soak them when I brought them home after finding them. I have no idea about how to prepare a fossil, but I would like to learn. I hear about airpens and different chemicals, what are they used for and where do I get them from? I have lots of partial ammonites which are very common and so would be safe to practise on.

I'm very new to all this, I'm afraid I don't have as much knowledge around fossils as I should have for a collection of this size.

Thanks

[Auspex]

It would benefit from being stabilized by treating it with a thinned consolidant; the information on this link should help: LINK

[Kosmoceras]

This is typical preservation of these trilobites I have seen, Moroccan in origin. Calymene or alike genus, I am unable to tell.

Sorry I can't help you with the prep.

Regards,

[dragonzrmetal]

Thanks for the replies so far. Does this mean it hasn't been prepared atall?

Does preservation refer to how it has been preserved during fossilisation, or how it has been prepared after extraction?

The link looks interesting. I didn't expect something as simple as a thin PVA to be used in preparing fossils. I found stabilisers made by PaleoBOND such as this one: http://shop.paleobond.com/PB002-Penetrant-and-Stabilizer-2-oz-PB002-02.htm That one seems to be made for ivory though, and I can't find a different one. I've heard of PaleoBond here before though, would it be reccomended?

PaleoBond also does this consolidant: http://shop.paleobond.com/PB4418-Pre-Prep-Field-Consolidant-2-oz-PB4418-02.htm

It talks about pre-preperation though; does this mean consolidation is used before preperation commences? I'm awfully new to this and frankly I'm somewhat confused about the process.

[Auspex]

In the UK, the most readily available consolidant seems to be Paraloid. Check with Ken Manion: LINK

A fossil's 'state of preservation' usually refers to how well it was treated by the earth; 'preservatives' are employed as part of preparation, to insure the specimen's longevity.

[Ptychodus04]

Preparation is simply removal of matrix and stabilizing as needed. That being said, you can have many states of preparation on different fossils and all can be considered "prepared". Sometimes, the prep only requires matrix removal. Other times it is far mor extensive. I have a similar Moroccan trilobite in the same condition. The cracks are just where parts are glued back on. Mine has cracks in similar spots and I have not applied any stabilizer. My trilo is in good shape and I have no plans to prep any further. Judging from your photo, it's certainly not going to fall apart on you. Kudos to your dad for salting the site in order to get you excited. That's great!