Prep Conulariid

[DPS Ammonite]

How should I prep this 6 cm wide crushed conulariid that is covered in a massive bryozoan and is from the Pennsylvanian Naco Formation of Arizona? It is only the second one that I have found. The matrix is a shaley limestone and is full of bedding cracks. Flakes are falling off either side of the fossil. I would like to take most of the matrix off the back side by hammer and chisel along a bedding plane 1-2 inches below.

 

I can make any thickness of Butvar B-76 solution in acetone. I am afraid that covering the conulariid with Butvar might not hold it together if I try to split the rock and inch or so below the fossil.

Edited October 10, 2023 by DPS Ammonite

[SPrice]

I'm still new at all things fossils...but this thread may be of assistance. It sure looks like it would work.

 

 

[connorp]

I would guess if you try to split the bedding plane, the crack will misdirect right through the fossil. Why? Because that's always what happens - Murphy's Law

What I have done before: consolidate the whole piece. Then use a dremel with a diamond bit to cut down to the bedding plane from the back, and pop off small squares of matrix. Much slower but safer than hoping the bedding plane splits nicely.

[rocket]

I would try to prep it with an airpen at low pressure with a really fine tip

and use superglue if something spreads away

never prepped material from this site, but this would be my first idea I would try

[Ptychodus04]

On friable matrices, I drop thin cyanoacrylate into the cracks to consolidate the entire block. Then, prep with a scribe/abrasive under high magnification. When done, you can trim the slab with a tile saw/grinder with a diamond cutting wheel. If you want to thin the slab, cut lines in the back to the depth you want about with 1/2" spacing and use a hammer/chisel to knock off the strips. Splitting the slab never works the way you want it to as @connorp mentioned. I've ruined a few fossils learning this lesson.

[DPS Ammonite]

Thanks everyone. Since I have Butvar, I will start by soaking it into the rock. Then I might take a really small chisel and try to break the rock along a crack. If the conulariid breaks then I will glue it. 
 

Up until now, most AZ fossils that I collected needed no fancy electrical prep tools.

Edited October 12, 2023 by DPS Ammonite