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Hi - I’ve had a hard time locating museum quality butvar - most particularly the the high molecular weight versions B-98. Could anyone point me to a source that could supply in less than large bulk quantity? many thanks in advance.

Hello, I'm a newbie. I'm looking for advice on what product to place on the fossils in the boulder below. I want to stabilize them in the matrix before I do any more removal. The photo with the (5) had a great rib in it but crumbled upon getting the rock into my truck. Fossils are exposed on many sides. As I began removing matrix with my Dremel 290, more fossils were uncovered. I read many articles and posts about solution adhesives. I want to keep it simple. I found premade Paraloid B-72 Glue, and the more complicated acetone and b-72, b-76 pellets. I may try and use a filler on my rib (1) that has a crack. This has been a great COVID hobby for me. My science students will get fossil remnants from me as student of the week rewards. Suggestions welcomed.

Found a paper today using Paraloid B-72. It’s a very useful read for any that prep

I’ve tried searching through the forum and it seems that there are mixed reviews about using paraloid on wet specimens. I have a couple of chunks of wet sand/clay with bivalves and gastropods that are extremely fragile. Everything will crumble with the slightest touch. So, what is the general consensus on using paraloid on wet specimens? Should I risk it and dry them out first?

Can anyone tell me whether this kind of glue (B-72) will hold up under freezing temperatures? I had the idea to prep out one of my local shale fossils using the freeze-thaw method, but I have glue in the part of the fossil that I want to keep intact. I don't want to subject it to freezing temps if the glue won't hold up. The plan is not to soak the whole piece, just apply a bit of water on the (unglued) side I want to freeze, either outside this winter when it goes below freezing, or in the freezer.

Heres how I prepare Paraloid b-72 for use as an adhesive and consolidant. Generally I use the approximate mixing ratios shown below which have been taken from a paper written by Amy Davidson and Gregory W. Brown called Paraloid b-72: Practical tips for the vertebrate fossil preparator, which can be found here: https://www.academia.edu/1237393/Paraloid_B-72_Practical_Tips_for_the_Vertebrate_Fossil_Preparator Approximate mixing ratios: Paraloid ratios.tiff However, if you want to create a solution of a known weight by volume percentage such as 20% (w/v) theres a trick. Since weight by volume solutions are worked out as the mass of the solid in the final volume of the solution, you need to know the volume of your final solution. For example if you had a 100ml bottle that you want to fill with a 20(w/v) solution of Paraloid what you would do is: 1) fill the bottle with 100ml of liquid. 2) mark on the bottle where the top of the liquid is. 3) weigh out the amount of Paraloid, which in this case would be 20g = (20/100)x(100 mL) as Mass of Paraloid = (Percentage of solution/100)x( final volume of the solution). 4) add the Paraloid to the bottle and fill with the solvent (acetone in this case) up to the 100ml mark. Say you wanted to make 2 litres of a 5% solution of Paraloid. You would follow the above steps replacing the 100ml with 2000ml = 2 litres. The mass of Paraloid would be (5/100)x(2000) = 100g. Note: it is important to keep you units consistent so if your volume is in mL your mass will be in grams. If your volume is in litres your mass will be in kilograms. Another form of concentration is a weight/ weight percentage, which is the percent by mass of the final solution where: Concentration of solution %(w/w) = (mass of solute)/(mass of final solution) This is a bit more complicated as you don't know how much volume of solvent to add or what the final volume would be. This technique is usually used to make big batches of the solution and is probably not all that useful for the weekend warrior. Hope this helps someone.