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Removing lacquer from fossils?


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I have to confess, I know virtually nothing about collecting fossils. I bought this little trilobite fossil for $14. It has some sort of glossy coating on it which I assume was done by another inexperienced collector in an attempt to preserve it. If I pour Acetone or paint thinner or something else on it and lightly brush it with a toothbrush to get rid of the coating, will that damage the original fossil material or the matrix?

 

Thanks.

Scott

 

Fossil:

$_1 (2).JPG

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A toothbrush might be a bit hard. If it's acetone soluble, I'd try washing it with repeated strokes of an artists' brush, dabbing the brush dry on a cloth every now and then and swabbing up the liquid..

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Acetone is the solvent to use.  I would test a corner first with a cotton swab to see if there are any issues and it comes off.  A caution if anything was done to the specimens, the solvent will also remove any paint touch up or repairs.  It's unlikely that anything was done but you never know. 

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Ok thanks ya'll.

 

I used to collect coins. If I told someone I wanted to clean a coin they would be all like "NO NO NO NO NO" etc...

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Wrangellian

I would clean a coin in acetone if there was some sort of plasticky or waxy coating (like your fossil might have), or in the ultrasonic cleaner if there was any other dirt or grime, otherwise no cleaning. They do lose some (or a lot) of their value if you strip any patina and you wouldn't want to lower the value of your collection, would you? When I was a kid we acquired some world coins from a late relative and I proceeded to strip the tarnish/patina off all the copper/brass/silver ones using Brasso and Silvo, and now I wish I hadn't.

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1 hour ago, Wrangellian said:

I would clean a coin in acetone if there was some sort of plasticky or waxy coating (like your fossil might have), or in the ultrasonic cleaner if there was any other dirt or grime, otherwise no cleaning. They do lose some (or a lot) of their value if you strip any patina and you wouldn't want to lower the value of your collection, would you? When I was a kid we acquired some world coins from a late relative and I proceeded to strip the tarnish/patina off all the copper/brass/silver ones using Brasso and Silvo, and now I wish I hadn't.

That's why I stopped collecting coins. Too much pickiness involved. I like the look of certain coins, but often I would be told they were inferior due to cleaning or some other "problem" that really meant nothing to me. 

 

I would however prefer to see the rock in its original clean state without any gunk on it.

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Wrangellian

You may be right about coins, but I can understand the admonition to not clean them when so many people don't know what they're doing (as I didn't back then), and the results I have to admit were not as good as if I had left the patina on them. I thought that removing the tarnish/patina would make them look newer. It didn't - it just made them look like the patina had been stripped off. A friend of mine told me about someone they knew or had heard of, who had a nice collection of rare US coins that he wanted to sell, and I guess it was a dealer who had agreed to buy them (over the internet I guess), and then when they were finally brought to the buyer he discovered that the guy had decided to run them through a rock tumbler to clean them, and the value was ruined. No deal!

I can't really understand why a decent cleaning job to remove gunk or verdigris should lower a coin's value, however. Just not Brasso or a rock tumbler.

 

To me, fossils are a little like coins - I want them as pristine and unaltered as possible, not polished or coated with anything. Gluing to stabilize a fossil is fine, as is prepping to remove matrix because you need to see the fossil, not the rock covering it, but there are aesthetically elegant ways to prep something, and then there are other ways.....

 

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Oh yeah, look into coincommunity forum. I was a member there (and still am i suppose) for about 2 years. The real "expert" collectors can tell if a coin has even only been dipped in a cleaning solution, let alone wiped clean. It really became quite annoying. Many would claim that even the nicest coins I had, ones that displayed lightning like cartwheel luster, had been cleaned, or that someone had it jingling around with their other change in their pocket for a few days, or some other mishap. It seemes like paranoid insanity to me.

 

I think I mostly just collected coins because I was bored at that time of my life, and I wanted to be a member of that particular website group. I don't really see fossils the same way though. If I got annoyed with what some group of people were saying about how fossils should be collected, I'd just leave and collect them my own way, because I'm truly fascinated by paleontology. I would like for a fossil to be as "original" as possible also - no lacquer, paint, enhancements, or alterations, but if it's something small and innocent it may not bother me.

 

Google searching this topic I read where someone claimed that acetone can soften or weaken rock, and that only rubbing alcohol should be used. I don't remember where the website was to give a link. Sounds fishy, but I still might just try alcohol before acetone when I get a chance. I had no idea what I was doing when I bought this fossil. I thought it was just a species with a weird looking head, but it's actually missing it's cheeks! Haha!

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8 hours ago, Wrangellian said:

You may be right about coins, but I can understand the admonition to not clean them when so many people don't know what they're doing (as I didn't back then), and the results I have to admit were not as good as if I had left the patina on them. I thought that removing the tarnish/patina would make them look newer. It didn't - it just made them look like the patina had been stripped off.

 

When I was in grade 5, I thought I was being clever in cleaning my coins. Apart from the coke trick, I discovered you could use the eraser end of a pencil, which functions as an abrasive. It stripped the patina and made it look newish, but never with that lustre you get from something authentically new. And it looks even more awful if the coin has any wear. And there is just no reliable way to replicate anything from MS-60 (let alone BU-70!).

 

These days, when I do the occasional appraisal, some will ask me before meeting if they should clean their coins - to which I say no if they are seeking to get value. Silver coins especially will have some degree of natural tarnish (even in some collector sets), but it definitely has to stay on to retain value. That being said, coins are better for collecting for enjoyment rather than as an investment as they do not appreciate in value at the same rate as that of inflation, generally (for a test, take a Charlton price guide from today and from ten years ago and compare the same coin price between the two: if the coin has not appreciated by at least 2% a year, then it is likely losing money in relation to the value of currency). Fluctuations in coin prices are very minimal (apart from melt values for certain metals), which makes them stable, but also not the most ideal investment vehicle. Prices change at a glacial pace, and there is certainly a wide gap between selling and buying prices.

 

Bottom line - in coins or fossils - unless one is a purist, collecting should always satisfy personal enjoyment irrespective of monetary value or the judgements of others. If people clean or enhance (or not) their stuff, that is a personal preference.

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Wrangellian

Agreed - but I guess the take-home point would be, if someone has any coins or fossils of any value at all, that if they want to sell them sometime down the road, they should consider how other people tend to like them, and minimal tampering is the safest bet, because once tampered with, you generally can't untamper! For instance, I like to leave a generous amount of matrix around my fossils when trimming. Others seem to like trimming almost down to the fossil, I guess because of space reasons (or shipping reasons when selling/trading). Once you trim, you can't add any back on.

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But back to the question.  If the trilobites are covered with dilute Elmer's, which is pretty common, acetone will do nothing.  Other coatings like lacquer and varnish, I m not sure it will do anything.       

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Wrangellian
4 minutes ago, jpc said:

But back to the question.  If the trilobites are covered with dilute Elmer's, which is pretty common, acetone will do nothing.  Other coatings like lacquer and varnish, I m not sure it will do anything.       

I have had some success with using a q-tip dipped in acetone to remove a thin layer of white glue (WeldBond) that has dribbled around the matrix of fossils I used it on, but these are thin films which remained after dabbing up the bulk of the excess, and there is rubbing involved. Maybe the amount of glue on this trilo (if white glue) will require too much rubbing to be worthwhile. But it could be tried.

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