Belemnite Preparation Tips

[ev_barr2]

I am wondering if anyone has any tips or guidance for preparing belemnite fossils. I found a bunch of them this weekend and would like to polish them so I can enjoy their orange color!

 

[grandpa]

Take the shortest specimen and place it in a very weak solution (1 tbls acid to 1 cup H2O) of muriatic acid (weak conc. of HCl used in pools and hot tubs) and watch it closely.  After 5 - 10 min (start with 5) pull it out and rinse it.  It should have a pleasant "polished" appearance.  If it is not yet "debrided" put it in longer.  If the surface is rough and pitted - it won't work - but at least you didn't choose the best specimen.

 

[N.B.  My experience with calcite (which the beleminite replacement is, if it is like what I've found at GMR,) is that vinegar etches the calcite and leaves a pitted, non-polished surface; while a weak solution of HCl (muriatic acid) leaves a smooth polished surface as it reacts with calcite.  I'll leave it to the geochemists in the forum to explain why that is, on a chemical surface level of detail.]

 

 

[Ludwigia]

If you want to do it by hand, use 5000 grit waterproof sandpaper to get a polish. As an alternative, you could coat them with a clear beeswax finish which can be polished up.

[Manticocerasman]

I use a color enhancer on my specimens that is normaly used for Marble. it works realy wel;

 

 

 

[TqB]

I'd say those look really nice and don't need rubbing down, it ruins their surfaces. A bit of beeswax will give a classy shine and enhance the glow. Maybe just rub down the most worn or weathered ones?

[Ptychodus04]

I’ve polished several belemnites in the past. If they are pitted, start with 250 grit and wet sand the test subject until smooth. Then move to 300 grit, then 400, 500, and finish with 1,000 grit (all wet sanding to eliminate the fine dust). At this point, it will be completely smooth and a dull finish. If you have a bench grinder, use a polishing wheel and a polishing compound like jeweler’s rouge to put a shine on it. If not, then proceed to the 5,000 grit abrasive as @Ludwigia suggested.