Hello Steve, attached is the receipe. This is what we use on our own personal items and our customers. On the receipe it gives a starting point on the mixture. This can be to a certain degree changed to suit personal tastes. The whole object of this is not to have to thick of mix. What one is after is penetration not just a top covering. The over welming highlites of using this receipe is the artifact will stay exactly as it was found....meaning if it was dull it will still be dull, if shiny, it will be shiny. It would look exactly as it was found. It also dries in literally seconds because of the high content of Acetone. One can actually hold the artifact as it dries.
This receipe is for "DRY" items only!!!!!!!!!!!!! Items still wet or from underwater sites require a different procedure to get from wet to where one can get the glue to go in. We recommend having someone familiar with that process to seal those items, whether us or another restorator that deals in that. It is not a difficult process but the advantage for someone very familiar with the process they know what signs to look for along the way that something is not going right and what to do to remedy the situation. "Dry" bone, shell, small pottery projects anyone can get a outstanding result.
The second most important thing is to "PRACTICE" on some dry scrap bone, shell, pottery shards, etc., first to get the feel of the process. I recommend mixing different percentage mixes as then one really can see the difference and what will suit them. Being in Florida whet bone artifacts are abundant and the marjority we do are WET items, as in recent finds. About the only dry ones we do here are past finds that have survied drying out already in colletions. We have used this procedure on some of the most premeier bone and shell collections in this state.
It is a poor mans way of doing the same thing the marjority of Universities use in theire sealing projects. They normally use Butvar 76 and Acetone. It works exactly the same as the Duco does but its draw back is Butvar is only sold in 10 lb bags unless one has a source that can sneak you out some stuff through the back door.
10 lb of Butvar is good for sealing a whole Mastadon but would last a normal collector a life time. This allows one to buy a small quantity cheaply and conveniently.
We are like car painters in the fact that we do so much of this type of work we actually mix by sight and not measurements (that just shows its not that critical on the mix to a certain point). We mix in a clear glass container normally with a lid but this can also be mixed in a open contatiner but evaporates fairly quick in a large mix producing vapors not good for comsumption on a regular basis as we do it. That is why for like a whole Mastadon tusk this is not the procedure to use for those large items. Even though the glue is clear and the acetone is clear one can see the two separately when initially mixed. The glue being thicker before being stirred can be seen. That is normally how we mix just becasue of how much we do and know what we are looking for.
When the artifact to be sealed is submerged 99% of items will begin releasing air bubbles, some slowly, some fast. We prefer to leave the items in the mix until all bubbling action has ceased (this normally is still only minutes). Then just take the item out and it will air dry in seconds.
One last comment : If the item one is sealing though seemingly dry has any moisture left in it especially near the surface a White residue can appear and is the reaction of the Acetone to water content. Do not be alarmed as after it is dry one can take straight Acetone and lighly wipe these areas and the residue will disappear. The glue embedded in the object will not be affected.
There is more I could type about but most meaningless stuff to the main job at hand.
I use to think I was a very good judge on what items needed sealing versus non-sealing. I have two bad memories that come to mind on my personal items that makes me seal all perishable items regardless of my thoughts. I watched a 6" Bone weaving tool start falling apart the moment I dug it up off a Ft. Ancient site in Tenn long ago. At that time there was nothing I knew to prevent that. The correct thing to have done was to get it back wet quickly and keep it wet till one could get it to someone who knew how to seal "wet" items. It could have stayed in water forever and not hurt it.
Here in Florida I had dove a spot that produced on that dive 5 whole bi-pointed bone pins in the 5" range. I took them to work (when I had my engineering job) so I could admire them as I worked. Towards the end of the day I noticed some small seeminly flakes of dirt....within 30 minutes those flakes starting being strips of the bone itsself looking like it was being peeled with a open knife blade! LOL
I still have the pin but it is 1/8 " thinner than it was originally as all the outside fell off. I did seal it but I keep it around close to remind me of what I should do. Again had I any sense at that time all I would have had to do was just get it back in water and it could still be whole today. Ivory items are even less forgiving and once that start exploding there is nothing that can be done to stop it, juts because of the make up of Ivory versus bone.
This is why we give the advice and this receipe freely to people as there is no need for any perishable item to be destroyed.
PS: This will also work on ancient wood items.