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I live in Perth, Oz and have called every hardware store and hobby shop. I've scoured the internet but still can't find any Butvar-76. I've fired off an email to the local museum but it may take days to get an answer. Any Aussies here that know? The Aus $ is REALLY low right now and shipping is a killer. I need a local source! Please help! (PS. I'm very new to the fossil collecting and from reading other posts on TFF this Butvar-76 appears to be the best stuff.) I'll pay US costs if I have to cause i love my fossils to bits. Hence the need for a consolidant, but has to available somewhere here!

Let me start out by saying I am not a fossil preservation expert, nor a paleontologist. I have a PhD in Paleoclimatological Modelling and as a consequence, spent my time glued to a computer, with my head deep in computer science and geological papers but not the rocks. My undergraduate honors thesis however was in paleontology, determining a metric for characterizing patterns in evolution using the morphology of Conodonts and Archosaurs... so I've always had a love for the field and have taken up fossil collecting again as a hobby now that I have found some time. Thought my recent head-first dive into fossil consolidation using Butvar-76 could help given the fact that a lot of newbies, such as myself, bring up the topic often and repeat the same questions. So, my effort to consolidate the information (pun intended) is here. One of the things I began researching was preservation of various material - bones as well as other delicate fossils as I wanted to preserve what I had collected and subsequently neglected over the years, until now. Clearly, consolidants such as Butvar-76, Vinac and PVA were regular hits in my research. My own decision was to use Butvar-76 simply because it was (or still is?) a standard in preservation and fully reversible if so desired. You can make your own decision to what best suites your own needs, but my write-up here is for my experience using Butvar-76. My initial research focused on these specific forum topics: http://www.thefossilforum.com/index.php?/topic/3629-preserving-fossils/ http://www.thefossilforum.com/index.php?/topic/23262-butvar-76-bone-frosting-solved/ http://www.thefossilforum.com/index.php?/topic/21591-butvar-vs-duco/ http://www.thefossilforum.com/index.php?/topic/35626-cleaning-and-stabilizing-st-clair-fossil-ferns/ http://www.thefossilforum.com/index.php?/topic/32206-where-to-buy-butvar/ http://www.thefossilforum.com/index.php?/topic/28135-butvar-b-76-question/ Harry's responses have always outlined exactly what I was looking for and he has a great write-up which I used as a basis for my first attempt: http://www.thefossilforum.com/index.php?/user/42-harry-pristis/ My first prep. and preservation was to be on a baleen whale jaw section and vertebra from the St. Marys formation around Calvert Cliffs. It was collected 12 years ago (roughly) and still had a lot of dried out clay material and shell frags embedded in it which I wanted to remove and some portions broken apart either during collecting or drying over the last decade. The bones fresh out of storage. Baseball for scale. The points Harry and others drive home is that Butvar is for impregnating. You can mix it up thick for a glue or for a demi-shellac, but technically for vertebrate material you want to soak the stuff - completely impregnate the bone with plastic by allowing the Butvar to seep into every pore and crack in the piece to consolidate it so that your precious finds wont dry out and crack over the years. If you are just starting out, like I was, I highly recommend reading Harry's write-up I linked above. For those looking for a shellac type substance, a different thickness in Butvar solution will accomplish this leaving your piece with a wet-like finish (a thin coat of solidified, fully reversible plastic). The look of the finish will depend however on your solutions viscosity (how much Butvar powder you dissolve), the amount of water in your material before application (this is bad) and how quickly you let the material evaporate. Personally, I wanted to keep my pieces as natural as possible without a shellac, but with the protective qualities of plastic impregnation. When you purchase your first Butvar-76 batch, expect it to come in a form similar to this. Powder. The things to watch out for, and pay attention to were: (1) Water such as surface, humidity, pore, interstitial etc; (2) evaporation rate of the solution after application; (3) thickness of the solution; (4) Materials for mixing (e.g. acetone can chew through lots of different kinds of plastics); (5) Storage. For the jaw section, I cleaned it using a soft toothbrush and water and left some of the clay material in some of the cracks that I thought would help stabilize the bone - for filling other cracks after the pieces were assembled I intended to use matrix mixed with white-glue. I did not glue the two larger pieces back together yet as I wanted to Butvar them separately as the acetone may weaken the glue. Since I used water for cleaning, I put the bones in the oven on low for an hour to dry them out. I read about heat shock damage, but many threads say they never experienced them, so I took a shot. I did however buy a few pounds of silica based desiccant (very cheap at pet stores and Ebay) for a homemade desiccant chamber just in case - and something I will touch on later for another piece to dry it out. Silica gel desiccant for drying items out that you don't want to put in the oven. You must create a very closed system for this. After drying, I used a 800 ml mason jar to mix my Butvar solution. My jars were acquired at the local Weis store and were less than a dollar a piece. The inner rim has a silicone based sealant which gets degraded with use - but since the jar is beveled and has the classic two-part top, you can still get a very tight fit without the spills. To mix, I measured the Butvar powder out and sprinkled the powder into the acetone. I then tightened the lid and shook violently until the powder became almost dissolved into the acetone (you will notice the white powder starts expanding into "clear bubble like" globs before finally fully dissolving into solution. I then left it for about 5 minutes to allow it to fully dissolve - and shook more if necessary. I made sure to check the bottom of the jar to disrupt any powder that may have settled to form a layer. Be rough with it. 800 ml Mason Jar. Mason Jar classic top, with beveled edge. This silicon gel sealant will get eaten by the acetone. If you are using a classic mason jar lid however, that doesn't matter if you tighten the top. I tested different thicknesses on random clean, dried rocks to see the different results. 1 tablespoon in 800 ml seemed to do very little. May be good for a deep soak but was hard to tell how much stability I was getting. At 3 tablespoons shale was getting a wet-like surface and at 3.5 tablespoons I was getting a clear coat on the outside that was painfully obvious. I didn't like this result personally, but my friend liked it on his St. Clair material as it made the shale darker, and ferns whiter. I will touch on this point again later on. Finally, after a bit more trial and error, about 2 and a third tablespoons seemed to be my sweet spot. Fractures were consolidated in shale, and smaller bone frags I had laying around definitely benefited. The outside also wasn't too obvious although when you touched it, you could tell ever so slightly that it was there. I then created a tin-foil pan using heavy-duty tin-foil, placed the bones in the foil pan and covered it with my solution. After about 30 seconds to a minute, I removed the pieces and placed them into a Rubbermaid PP recycle number 5 container to slow down evaporation. Earlier, without tenting the material, a bone fragment got the white dusting on the outside that had to be removed with acetone later on. I wanted to avoid this. It should be noted that not all plastics are created equal and there are many out there that can fit the bill here for both soaking (if you don't want to use tin-foil) and tenting to slow down evap. I used the following to allow me to find the right materials for this job: http://www.coleparmer.com/Chemical-Resistance http://www.plasticsintl.com/plastics_chemical_resistence_chart.html Simple Rubbermaid storage container - singular unit PP 5 plastic. Recycle number 5, PP, is Polypropylene and is A-Excellent for compatibility with acetone. Lots of Rubbermaid tubs are made from this but make sure to check - LDPE is not very good and after a few uses will start to degrade. Recycle number 3 will simply dissolve. Silicone also will degrade which is often used in lids including the popular Pyrex home storage container lids. My container was a singular piece PP box. I added some tin-foil balls to the base of my box for drying purposes, as I wanted to have less contact points on the incoming wet fossils - the balls act as pedestals over the plastic which seemingly helps drying on all sides - and the natural crinkles in the foil further reduce contact points. Super-dee-duper simple drying rack. Tin foil balls placed in the bottom of the PP5 container. The balls act as a colonnade to stack your fossils on to reduce contact points while drying. The crinkles in the foil further reduce surface area touching the specimen. Fossil stacked for drying, tented for slower evaporation of the Butvar solution. After tenting and allowing the bones to fully dry, I glued the fragments back together with cyanoacrylate gel (super glue) and am beginning the process of finalizing the finer details using white glue and matrix. Any "frosting" you get due to whatever process you use, can easily be removed using a q-tip or brush dipped in acetone. The amount of pure acetone you will re-apply depends on what you are doing - if you are re-soaking in acetone to remove the plastic (or some of it), or simply adding some acetone to try and get the plastic back in solution to seep deeper off the surface. Current prep. state of the same bone material. Brown coloration coming through after cleaning, fully impregnated with plastic. No frosting and pieces are re-assembled using cyanoacrylate gel. Cracks will be filled in with a mixture of the calvert clay and PVA. For brushes I used a Nylon based brush as Nylon does not react with acetone. You can get natural hair brushes from an art store, but Home Depot had artificial bristles, Nylon of which was the most compatible with acetone. Simple Nylon bristle brushes - thanks Home Depot. Nylon has a high level of acetone compatibility. Other artificial bristles will dissolve. For impregnation I poured over the entire bone. Brushes were used on smaller pieces to drip solution over. I rarely brushed - I may have dabbed here and there especially over areas of bone that had more pores in them to help the solution to get into the material. These brushes can be used in pure acetone to re-dissolve Butvar, or clean up and frosting which may have occurred in your own experiences. Every thread regarding Butvar talks about bones because that is seemingly the primary use. Agreed. However, I wanted a material that could be used almost universally for archival purposes, vertebrate and invertebrate - even on St. Clair shale. 14 inch St. Clair plate, multiple species, pre-Butvar. Fern fossils from St. Clair are very intricate and have both a graphitic like imprints and the famous white Pyrophyllite form. The later of which flakes off easily even as you try and get it out of the field site. I wanted something that could preserve the ferns, Pyrophyllite and all, as well as consolidate any shale layers and frags that may have been loosened during excavation. The Pyrophyllite also seems sensitive to water content so I wanted to completely preserve the piece. People have had success using hair-spray in the field (cf. links above) and in hind sight, I probably would use a soluble hair-spray in the field for removal, bring the fossils home, rinse with water, dehydrate, then consolidate. In my first attempt however, I skipped the hair-spray and brought them home the best I could. Since I didn't want to "cook" shale from a high carbon locality, I took the silica desiccant, filled a porous sack (feel free to use a sock) and put it in another Rubbermade container. I then left the fossils inside this home-made desiccant chamber for 2 days, only to remove them immediately prior to Butvar application. It's not perfect, but I like to think it did something - the Rubbermade get's a very good seal to it, proof of which is the fumes of acetone when you finally open the lid. Along these lines an important note: make sure to always do this in a highly vented area (outside is good) and no where near anything flammable. At 3.5 tablespoons of Butvar in my 800 ml container my friend got a wet-like clear coating on the outside of his pieces which he liked as they made the shale blacker and the white ferns pop more. And clearly they were preserved. I wanted something less obvious and went with my 2 and a third tablespoon mixture again and followed the same procedure outlined above. The outcome was perfect, with layers and fragments firmly in place, the shale still in its original color and I can tell that the piece is Butvar'ed since I can rub my finger on the pieces and not get an anthracitic stain on my figure from the residue of the shale. Also, the white portions no longer flake on contact. Putting a non-consolidated shale piece next to one I did at 2 and a third tablespoons, you cannot tell the difference. Same plate as before, after Butvar using the solution ratio mentioned. A lot of this was trial an error using the aforementioned posts as a guide. I am sure the heavies will chime in on the mistakes I made along the way, but thought first timers may enjoy a report on a fellow first timers attempt. And Harry, if you feel I lead someone astray with some wrong information, I will gladly correct my wording - or point out my own mistakes. Best, M