Shellac or not? Help requested.

[HFVC Fossils]

Hey, I've seen this guys videos before and wondered your thoughts or feedback on his fossil preservation techniques. Thanks!!

 

 

[caldigger]

The only reason I would put something like this on a fossil is if it was in grave danger of disintegrating.  Are yours in that kind of shape?  Also that plastic look given to the pieces in the video really ruin the look for me.  Natural polishing is the only shine I like to see.  That's my opinion, you may feel differently.  Also keep in mind, some shellacs turn yellow after time.  If I were to do this, I would chose a more matte finish.

[HFVC Fossils]

I have at least a handful of vertebrate fossils that were stored at my mothers house from college days collecting that have a bit of ??sulphur?? rust forming.  One was made soft from it, or just became soft due to ??

 

so i am wishing I had done something. Makes me worry/be concerned with my other fossils.  Wash them well, then do something to semi-lock out moisture and oxygen.  

Yes/no?

[Fossildude19]

Do a search on the forum of Paraloid or Butvar. You will find lots of information on stabilizing fossils with them - it is well covered ground here.

Regards,

[Ptychodus04]

Don't use Elmer's or shellac on fossils that you want to keep looking nice for more than 10-15 years. Both become brittle and yellow over time. Very bad.

 

The "sulfur rust" is what is known as pyrite disease or pyrite decay. Many vertebrate fossils contain some degree of pyrite (iron sulfide). Over time, the moisture in the air reacts with the pyrite and creates a weak sulfuric acid. This proceeds to destroy the fossil in a slow, painful way...

 

Thankfully, pyrite decay can be halted or prevented with proper treatment. There are a few ways to do it. Here's my favorite.

 

Mix a cup of Iron Out with 1 gallon of hot water. Stir until dissolved. Soak fossils for at least 4 hours (overnight better). Scrub the fossils with dish soap and a toothbrush. Rinse fossils well. Allow to dry for 24 hours or bake in oven on lowest setting for a few hours. Procure some PVA, Butvar, or Paraloid and mix with acetone in a ratio (by volume) of 50:1 acetone to plastic. either soak fossils in the solution until bubbles stop coming out or brush on several coats of the solution. Allow to dry completely.

 

This will stop the pyrite decay and preserve your fossils for your grandchildren's grandchildren to look at.

[caldigger]

Ya, sorry I have no experience with pyrite decay, I guess we don't suffer the same humidity effects here as you kids do in the southern states. "It gets hot, but its a dry heat".

Hope you find a satisfactory solution.  Cheers.

[JohnBrewer]

Why use products that aren't used by professionals/museums etc in paleontology when there are proven archival adhesives and coating compounds available? They're not expensive either. 

[Ptychodus04]

45 minutes ago, JohnBrewer said:

Why use products that aren't used by professionals/museums etc in paleontology when there are proven archival adhesives and coating compounds available? They're not expensive either. 

 

Inferior materials and methods continue to be used because most people don't do what the OP did here and ask the question. I'm sure many people watch the YouTube video and just follow instructions, never questioning whether or not this is the right way. This is one of the traps of our social media generation. Any idiot can post something online and pretend to be a subject matter expert.

 

...wait, I just posted instructions on line claiming to be a subject matter expert.

[HFVC Fossils]

5 hours ago, JohnBrewer said:

Why use products that aren't used by professionals/museums etc in paleontology when there are proven archival adhesives and coating compounds available? They're not expensive either. 

Well the fear would be that those products are very expensive. The second thing would be choosing the best product for your items from maybe a big selection of products. Third, there ARE expensive products that 'are just marketing'.  And for some people, who aren't that adept online, ordering something from Amazon or a supply store is not near as easy as Walmart.

I will do some searches, but if you can provide a list that would be extremely helpful too. 

-Fresh finds, vertebrate fossils:

-fresh finds, invertebrate fossils(petrified)(probably nothing!? Very shelf stable):

-fresh finds, shells, possible brittle:

-each of the above, old finds, no noticeable degredation

-vertebrate with pyrite rust (already covered by Pytchodus04)

 

Also, if there is one product fits all, that is best.  Or two products, that will do for all/nearly all, will be most helpful since I AM on a tight budget. 

 

thanks!!!

[Ptychodus04]

On 9/22/2016 at 7:07 PM, HFVC Fossils said:

Well the fear would be that those products are very expensive. The second thing would be choosing the best product for your items from maybe a big selection of products. Third, there ARE expensive products that 'are just marketing'.  And for some people, who aren't that adept online, ordering something from Amazon or a supply store is not near as easy as Walmart.

I will do some searches, but if you can provide a list that would be extremely helpful too. 

-Fresh finds, vertebrate fossils:

-fresh finds, invertebrate fossils(petrified)(probably nothing!? Very shelf stable):

-fresh finds, shells, possible brittle:

-each of the above, old finds, no noticeable degredation

-vertebrate with pyrite rust (already covered by Pytchodus04)

 

Also, if there is one product fits all, that is best.  Or two products, that will do for all/nearly all, will be most helpful since I AM on a tight budget. 

 

thanks!!!

 

This is actually easier than one would think. There are two schools of thought on fossil stabilization.

 

1. All fossils need to be stabilized

2. Only some fossils need to be stabilized.

 

I'm a hybrid of both schools. IMHO, all vertebrate fossils require stabilization as they often contain some traces of pyrite and even the most stable bones can randomly become unstable for no reason it seems! Only some inverts require stabilization.

 

Fossils can be stabilized using PVA, Butvar, or Paraloid. All are readily available online. Dry fossils, make a solution of the plastic dissolved in Acetone or Denatured Alcohol. Wet fossils, would require controlled drying (detailed processes mentioned in other posts on the forum) or the application of a suspension of the PVA, Butvar, Paraloid solution. If drying can be done without damage, that is the preferred method.

[JohnBrewer]

On 23 September 2016 at 1:07 AM, HFVC Fossils said:

Well the fear would be that those products are very expensive. The second thing would be choosing the best product for your items from maybe a big selection of products. Third, there ARE expensive products that 'are just marketing'.  And for some people, who aren't that adept online, ordering something from Amazon or a supply store is not near as easy as Walmart.

I will do some searches, but if you can provide a list that would be extremely helpful too. 

-Fresh finds, vertebrate fossils:

-fresh finds, invertebrate fossils(petrified)(probably nothing!? Very shelf stable):

-fresh finds, shells, possible brittle:

-each of the above, old finds, no noticeable degredation

-vertebrate with pyrite rust (already covered by Pytchodus04)

 

Also, if there is one product fits all, that is best.  Or two products, that will do for all/nearly all, will be most helpful since I AM on a tight budget. 

 

thanks!!!

 

Paraloid pellets, acetone and ethanol. You should be able to use Everclear as your alcohol. By varying the proportions of these you should cover all bases. Check the large auction site or good fossil dealers for the Paraloid pellets. While you'll be able to buy premixed Paraloid it's much better to mix your own because a) it's probably cheaper and b ) it will give you infinite variations. 

[HFVC Fossils]

Ok!!! It's not ~cheap~, but I decided to take the plunge. I just bought 500g of Paraloid off ebay. I had cash in Paypal, so that helped. Everclear isn't cheap and we don't keep it around....so I'm guessing hardware store for Acetone.  

Ok, let's see how this goes!!

[Wrangellian]

I don't know about vertebrate fossils, I'm an invert guy, but I'm with Caldigger: whatever method you use, it is preferable to avoid the glossy finish. You might like it yourself, but someday your fossils might end up in someone else's hands (or a museum) and they will wish you hadn't done that. Glossy makes it difficult to photograph should you ever need to do that. What I like about white glue diluted with water is that it doesn't dry instantly like some of the other glues, and is easy to dab off the excess before it dries, with toilet paper, though in warm sunny weather it will start to dry around the edges quickly and you are left with thin lines of gloss around the edges of the glue, but this can be removed with a little water and rubbing (eg. Q-tip).

If the specimen is cracking but is not one that you have to worry about pyrite disease, then you only need to get the glue into the cracks, then wipe any remaining glue off the outer surface. Then it should be stable long-term, and still look natural.

[JohnBrewer]

500g will last several lifetimes unless its massive dinos you're dealing with!

 

Grab some clean empty bottles, try a pharmacy, and make a few strengths up. Stick to acetone if alcohol/Everclear is difficult.  5g/95ml, 10g/90ml, 20g/100ml etc up to around 40/60. That's probably overkill, you could always just make up a 50% say stock solution and dilute as needed.   I use about 5g for coating, 20g for cracks and 35-40 for adhesion. Grab some junk rocks of different types and have a play. Try different strengths on the same rock and see what you get. Try it in cracks. Glue a broken one back together. Try different rock types. Post your findings here with images, we'd love to see your results. 

 

With acetone remember it dissolves many plastics like for example  bottles (use glass), synthetic paint brush hairs (use natural) and plastic syringes. I do use plastic syringes but fairly quickly a few minutes. 

 

Why acetone and alcohol? Acetone evaporates very fast so can be useful but when using as a coating say it can skin over. No problem, just dab it off with neat acetone. Alcohol evaporates much slower so can give you time. It's great for coating. It doesn't dissolve plastics. You can mix the two solvents if need be. You will need some acetone though when making up an alcohol mix as Paraloid is a complete nightmare to dissolve in pure alcohol. 

[HFVC Fossils]

Haha! Great, I bought too much!  ;-)

 

thanks for the tips and experiences!! This is exactly what I was hoping to hear!!!

 

let's see how it goes!!

[Ptychodus04]

16 hours ago, Wrangellian said:

I don't know about vertebrate fossils, I'm an invert guy, but I'm with Caldigger: whatever method you use, it is preferable to avoid the glossy finish. You might like it yourself, but someday your fossils might end up in someone else's hands (or a museum) and they will wish you hadn't done that. Glossy makes it difficult to photograph should you ever need to do that. What I like about white glue diluted with water is that it doesn't dry instantly like some of the other glues, and is easy to dab off the excess before it dries, with toilet paper, though in warm sunny weather it will start to dry around the edges quickly and you are left with thin lines of gloss around the edges of the glue, but this can be removed with a little water and rubbing (eg. Q-tip).

If the specimen is cracking but is not one that you have to worry about pyrite disease, then you only need to get the glue into the cracks, then wipe any remaining glue off the outer surface. Then it should be stable long-term, and still look natural.

 

 

I have to humbly disagree. PVA, Butvar, and Paraloid can all be readily removed/reversed with straight acetone. This allows one to greatly reduce any shine that the plastics impart while still using an archival grade consolidant. Diluted white glue can almost never be easily reversed once it had completely dried. Too many times, I have been asked to remove old white glue from a fossil and it's a nightmare. You have to soak the entire specimen for a week in acetone (praying the whole time that the fossil isn't unstable) and the spend hours scraping off sticky glue boogers. I would never recommend dilute white glue as a consolidant unless the specimens are wet and can't be safely dried prior to consolidation.

[Wrangellian]

My intent was not to recommend against the Butvar etc. Your method sounds good for what the OP was asking about. I guess I am so used to white glue that I find it easier to use, and can do so in such a way that I don't have to reverse it as often as I do Paraloid, and not leave a glossy coat, and when I do make mistakes in reassembling something I have time to just pull it apart and redo it before it dries, and can dab off the excess with TP (doesn't work on Paraloid). With Paraloid you have to keep adding acetone to undo it and remove the excess, and breathe those fumes...

[Ptychodus04]

I agree that a water based glue can be easier to use. Unfortunately, it is not good in the long run and will result in damage to the  specimen over time (eventually, our collections will go to someone else and they may want to remove the crusty yellowed white glue).

 

I also agree that the constant use of acetone can't be good for our livers! I always use acetone in a well ventilated area for this reason. If you use one of the plastics (PVA, Butvar, Paraloid) as a glue (with the right viscosity) it actually takes a few days for the solvent to completely evaporate giving plenty of time for placement of pieces. The process is admittedly more involved but they have proven to be stable and reversible for several decades where white glue cross-links rather quickly and becomes nearly irreversible and will degrade over time.

 

We only use Butvar as a consolidant and general glue in the prep lab at the Perot. Items that require more bonding strength get a slow setting epoxy.

[Harry Pristis]

11 hours ago, Ptychodus04 said:

 

 

I have to humbly disagree. PVA, Butvar, and Paraloid can all be readily removed/reversed with straight acetone. This allows one to greatly reduce any shine that the plastics impart while still using an archival grade consolidant. Diluted white glue can almost never be easily reversed once it had completely dried. Too many times, I have been asked to remove old white glue from a fossil and it's a nightmare. You have to soak the entire specimen for a week in acetone (praying the whole time that the fossil isn't unstable) and the spend hours scraping off sticky glue boogers. I would never recommend dilute white glue as a consolidant unless the specimens are wet and can't be safely dried prior to consolidation.

 

Don't be humble about it, Ptychodus04.  When you're right, you're right!  This idea of white glue as a consolidant is as persistent as it is misguided.  I am glad you're making that clear.  The newbies need to hear it. 

[Ptychodus04]

9 hours ago, Harry Pristis said:

 

Don't be humble about it, Ptychodus04.

 

“Humility is the only true wisdom by which we prepare our minds for all the possible changes of life.” - George Arliss

 

 

I try to avoid the "high horse" as it is significantly painful when one falls from it.

 

 

[Harry Pristis]

4 hours ago, Ptychodus04 said:

 

“Humility is the only true wisdom by which we prepare our minds for all the possible changes of life.” - George Arliss

I try to avoid the "high horse" as it is significantly painful when one falls from it.

 

 

 

The truly humble don't have to announce it.  It's easy enough to distinguish between arrogance and advocacy.  I was applauding

your advocacy, not criticizing your false humility.  Mount your destrier fearlessly, and carry on.

[Wrangellian]

21 hours ago, Ptychodus04 said:

I agree that a water based glue can be easier to use. Unfortunately, it is not good in the long run and will result in damage to the  specimen over time (eventually, our collections will go to someone else and they may want to remove the crusty yellowed white glue).

 

I also agree that the constant use of acetone can't be good for our livers! I always use acetone in a well ventilated area for this reason. If you use one of the plastics (PVA, Butvar, Paraloid) as a glue (with the right viscosity) it actually takes a few days for the solvent to completely evaporate giving plenty of time for placement of pieces. The process is admittedly more involved but they have proven to be stable and reversible for several decades where white glue cross-links rather quickly and becomes nearly irreversible and will degrade over time.

 

We only use Butvar as a consolidant and general glue in the prep lab at the Perot. Items that require more bonding strength get a slow setting epoxy.

Again, I was not talking about using white glue to slather a fossil and then have the next owner curse me for leaving the yellowed crust. I would only use it to fill the cracks, where if it yellowed you wouldn't see it. But if you can do the same with a plastic, then use the plastic by all means. About stability over decades, if that is actually true then I will concede, and I am trying to switch to Paraloid, but it is much more difficult to use in certain instances. What do you mean it takes a few days for the solvent to evaporate - it only takes seconds, I find, whereupon I need to apply more acetone to undo it. Is it not undoable after a few days?

[JohnBrewer]

Alcohol with Paraloid takes quite a while to evaporate, can be a couple of hours. Acetone as you say takes a few minutes which can be a blessing in the field but can also be a pain. Mixing acetone and alcohol can give you the best of both words. 

 

Regarding toxicity folks, look under your kitchen sink. You'll probably have sodium hydroxide. Read up on that. That's THE ingredient in drain and oven cleaner. Then there's the shed, paint stripper &c. It's all about taking the relevant safety precautions. Read the MSDS (manufacturers safety data sheets). 

[Wrangellian]

What kind of alcohol, ethanol? and what ratio, about the same of each?

Maybe someday I'll get the techniques down for every possible use, such that I can work with it as easily as I can work with diluted white glue, but it's already getting pretty complicated...

 

[JohnBrewer]

17 hours ago, Wrangellian said:

What kind of alcohol, ethanol? and what ratio, about the same of each?

Maybe someday I'll get the techniques down for every possible use, such that I can work with it as easily as I can work with diluted white glue, but it's already getting pretty complicated...

 

Yes, ethanol. It's really a matter of playing around a bit. Say 50:50 with acetone and 25:75 ethanol/acetone. I read that some people have used just Paraloid and ethanol but I've never got it to dissolve properly.