UV wavelength to detect restorations?

[Owl_Roker]

Hi All,

 

Quick question for you. What UV wavelength should I be using to detect restorations? Will repairs show up under 395nm?

 

Thanks.

[Troodon]

Here is a topic that discusses that.   You should focus your attention on the comments made by @aeon.rocks

 

 

[Owl_Roker]

6 minutes ago, Troodon said:

Here is a topic that discusses that.   You should focus your attention on the comments made by @aeon.rocks

 

 

Thanks a mil!

[aeon.rocks]

Yes, but... No too.  As mentioned, there's no good "universal" (fit for all fossils or restos) way to check for restorations with UV. UV can be a useful tool in determining restoration, but not as simple as "if it glows, it's restored, if not, it's natural". The best way to check for resto is with magnification (and a sandblaster, if one's at hand), but since the best restoration is sometimes made from authentic donor composited parts and some materials don't show in UV - interpreting a possible restored area comes down to the interpretation of how the fossil in question was prepped (maybe better to say "how and why restoration was done") and experience with preservation of specific details of specie/locality/layer (diagenesis)... It can get quite difficult to spot restoration, if done professionally and "tricky" materials are used, unless you've held several authentic specimens of fossils in question in hand (and even then).

 

So the question you should be asking is: what fossils do you want to check for restoration (some details are more tricky to restore than other, knowledge about morphology and fine details of different species/fossils can help - if they were preserved in prep) and how much restoration is acceptable for you (in example, with megalodon teeth or pet wood collectors usually 0% is acceptable, not even glued parts; with trilobite or ammonite collectors some small resto % and glued parts are normal - a lot comes only down to (re)sellers you trust in the end). If you're worried about resto on trilobites, this might help to show the good and bad examples. Mostly written about fakes, but same observations apply to resto and there's nice examples of poor and well restored bugs.

[Owl_Roker]

14 hours ago, aeon.rocks said:

Yes, but... No too.  As mentioned, there's no good "universal" (fit for all fossils or restos) way to check for restorations with UV. UV can be a useful tool in determining restoration, but not as simple as "if it glows, it's restored, if not, it's natural". The best way to check for resto is with magnification (and a sandblaster, if one's at hand), but since the best restoration is sometimes made from authentic donor composited parts and some materials don't show in UV - interpreting a possible restored area comes down to the interpretation of how the fossil in question was prepped (maybe better to say "how and why restoration was done") and experience with preservation of specific details of specie/locality/layer (diagenesis)... It can get quite difficult to spot restoration, if done professionally and "tricky" materials are used, unless you've held several authentic specimens of fossils in question in hand (and even then).

 

So the question you should be asking is: what fossils do you want to check for restoration (some details are more tricky to restore than other, knowledge about morphology and fine details of different species/fossils can help - if they were preserved in prep) and how much restoration is acceptable for you (in example, with megalodon teeth or pet wood collectors usually 0% is acceptable, not even glued parts; with trilobite or ammonite collectors some small resto % and glued parts are normal - a lot comes only down to (re)sellers you trust in the end). If you're worried about resto on trilobites, this might help to show the good and bad examples. Mostly written about fakes, but same observations apply to resto and there's nice examples of poor and well restored bugs: https://www.trilobiti.com/post/are-trilobites-rare-or-common-fossils

 

This is really helpful. Thanks for taking the time to respond @aeon.rocks

 

Re your comment about acceptable restoration thresholds (i.e., 0% for petrified wood and megalodon teeth, minor restoration for trilobites/ammonites, etc.), I was considering the below Zamites. You can see there is a repaired crack running through the bottom of the rock and the fossil. I'm new to collecting, so I would be curious to know what the wider consensus is on restorations on plant plates of these nature. As an experienced collector, would this specimen be a "no-go" for you due to the restoration work? It isn't very expensive and I think it's nice looking, but I'm obviously weary of the repaired crack.

 

Grateful for your thoughts.

 

 

 

Edited June 14, 2020 by Owl_Roker

[aeon.rocks]

 If you ask me, all the fuzz about restoration or repair (repair and restoration are different words with different meaning by definition btw) in the fossil collecting world is (almost!) just nonsense (unless you are a new collector worried that you'll overpay), but you'll need to figure out if that glued crack distracts you from purchase or not by yourself... Keep in mind, it's fossils we're talking about, millions of years old, not a toy (that you throw away if it breaks and buy a new one).

 

I quit purchasing fossils long ago, with few exceptions here and there, but personally I'm not against restored or repaired fossil or replicas, if there's a good balance... The only problem I see is when collectors are scammed... In other words: what's the point to complicate the fun of collecting by demanding/collecting only natural (0% restored and 0% repaired) fossils, if we then end up purchasing i.e. polished Madagascar ammonites (which are far from the natural state in which they are found), or buffed megalodon teeth (cleaned shiny with a buffing wheel and not in a natural state as found), or the cheapest "natural" trilobites prepped in massacred commercial way (with all fine natural details sent to hell in prep or even massacred to unrecognizable condition, that even experts can't ID) or cut and polished petrified wood (far from the "state as found")... Etc.! What is the point of "natural" fossils, when every preparation is a manipulation by itself and when at least 50% of fossils in commerce are merely decoration items or destroyed/damaged in preparation, but all novice collectors care about is "if natural"? A nice fake can look just as nice and enjoyable on the display stand, for the right price... And a well prepped and well accurately restored and repaired fossil in my book is by far a better choice, usually, as a massacred prepped natural one...

 

 Most fossils mentioned have no scientific value, very few collectors purchase fossils for study and I'm guessing this Zamites will end up on your display shelf, just like a polished Cleoniceras sp. would; so if the purpose is display or conversation piece, don't worry so much about restorations, but do learn to recognize and interpret them... Rarely fossils are found in perfect state and complete, unbroken or without missing or disarticulated, crushed parts... Who cares about "consensus", if the price is right and if you are limited to go to the field and collect yourself, you can online-collect what you like, not what others think you should. 

 

 It's not a question if repair/resto is a "no no", but if:  you like or not? Is the repair/resto well done and accurate or is it distracting and morphologically not accurate? Is it minimal or is half of the fossil restored and overpriced? Do you like the fossil despite the resto or not? 

 

Do you you prefer a well prepared, well repaired (or restored) fossil or a natural over-prepped, bad prepped fossil? Just a few questions to think about...

 

I'm more of a trilo-guy, so examples below are not plants.  Maybe that's also why I don't find the glue crack very distracting, with trilobites that's as natural as they come...

 

  Which one would you add to your collection, if the price was the same, left is well prepped natural, right aesthetically restored (the same specimen, before and after restoration):

 

Which one do you prefer on your display stand, the left or right one (one is a replica, one is real)?:

 

 

Or last example... Which one do you prefer? 

 

Natural without eyes:

 

 

Or restored and composited eyes:

 

 

 

 

What I'm trying to point out with this is: a lot comes down to personal opinions. 

[Harry Pristis]

 

Posted March 18, 2011

The wavelength of my LED device is 395 nm (nanometers), up at the high end of the UV spectrum.

Butvar-76 and Glyptal flouresce. Repairs with epoxy and epoxy casts flouresce brightly. Casts made of polyester resin do not flouresce. That is, in the wave-length produced by these LEDs.

 

As I mentioned earlier, epoxy resin flouresces but polyester resin does not. Here is a cast of a bear-dog maxilla made of epoxy resin colored with tempera pigments.

 

 

 

This is a cast from one of the first molds I made, so don't be too critical of the rendition. But, look at the way the epoxy flouresces in UVA!

 

Examination for authenticity is one of the prime uses for UVA (not to mention checking hand-stamps at your local concert or rave.)

 

I was surprised to find that polyester resin does not flouresce, though epoxy resin does. Among bottle collectors, for example, I would expect optically-clear polyester resin would be the repair material of choice, making UVA examination useless.

 

Body fillers like "Bondo" which use polyester resin as a binder would not flouresce.

 

But another dilemma has arisen. Epoxy repairs are very common in vertebrate fossil preparation. Vertebrate bones are often found in pieces, so patches, extensions, and joins are common. Perfection is appreciated in a vertebrate fossil; but, repairs are the norm, so such restoration does not much affect collector interest. (This is a somewhat different attitude than when dealing with invertebrates.)

 

The dilemma? . . . Some of my best, most esthetic vertebrate fossils look awful under UVA because of the lightning-streaks of expoxy joins and repairs!

[aeon.rocks]

Quote

Body fillers like "Bondo" which use polyester resin as a binder would not flouresce.

 

A very common used resto material, with pigments or acrylic, besides matrix sculpting and compositions, hence the limited use of UV as the only option for examination. Repairs when dealing with invertebrates are normal, but repair is not the same as restoration. Collecting fossils is like buying in a supermarket nowadays, so many dilemmas.

[Owl_Roker]

20 hours ago, aeon.rocks said:

 If you ask me, all the fuzz about restoration or repair (repair and restoration are different words with different meaning by definition btw) in the fossil collecting world is (almost!) just nonsense (unless you are a new collector worried that you'll overpay), but you'll need to figure out if that glued crack distracts you from purchase or not by yourself... Keep in mind, it's fossils we're talking about, millions of years old, not a toy (that you throw away if it breaks and buy a new one).

 

I quit purchasing fossils long ago, with few exceptions here and there, but personally I'm not against restored or repaired fossil or replicas, if there's a good balance... The only problem I see is when collectors are scammed... In other words: what's the point to complicate the fun of collecting by demanding/collecting only natural (0% restored and 0% repaired) fossils, if we then end up purchasing i.e. polished Madagascar ammonites (which are far from the natural state in which they are found), or buffed megalodon teeth (cleaned shiny with a buffing wheel and not in a natural state as found), or the cheapest "natural" trilobites prepped in massacred commercial way (with all fine natural details sent to hell in prep or even massacred to unrecognizable condition, that even experts can't ID) or cut and polished petrified wood (far from the "state as found")... Etc.! What is the point of "natural" fossils, when every preparation is a manipulation by itself and when at least 50% of fossils in commerce are merely decoration items or destroyed/damaged in preparation, but all novice collectors care about is "if natural"? A nice fake can look just as nice and enjoyable on the display stand, for the right price... And a well prepped and well accurately restored and repaired fossil in my book is by far a better choice, usually, as a massacred prepped natural one...

 

 Most fossils mentioned have no scientific value, very few collectors purchase fossils for study and I'm guessing this Zamites will end up on your display shelf, just like a polished Cleoniceras sp. would; so if the purpose is display or conversation piece, don't worry so much about restorations, but do learn to recognize and interpret them... Rarely fossils are found in perfect state and complete, unbroken or without missing or disarticulated, crushed parts... Who cares about "consensus", if the price is right and if you are limited to go to the field and collect yourself, you can online-collect what you like, not what others think you should. 

 

 It's not a question if repair/resto is a "no no", but if:  you like or not? Is the repair/resto well done and accurate or is it distracting and morphologically not accurate? Is it minimal or is half of the fossil restored and overpriced? Do you like the fossil despite the resto or not? 

 

Do you you prefer a well prepared, well repaired (or restored) fossil or a natural over-prepped, bad prepped fossil? Just a few questions to think about...

 

I'm more of a trilo-guy, so examples below are not plants.  Maybe that's also why I don't find the glue crack very distracting, with trilobites that's as natural as they come...

 

  Which one would you add to your collection, if the price was the same, left is well prepped natural, right aesthetically restored (the same specimen, before and after restoration):

 

Which one do you prefer on your display stand, the left or right one (one is a replica, one is real)?:

 

 

Or last example... Which one do you prefer? 

 

Natural without eyes:

 

 

Or restored and composited eyes:

 

 

 

 

What I'm trying to point out with this is: a lot comes down to personal opinions. 

@aeon.rocks, this is brilliant. Thanks for taking the time to provide such a comprehensive response. Really helpful. Lots for me to consider here!

 

 

[Owl_Roker]

20 hours ago, Harry Pristis said:

 

Posted March 18, 2011

The wavelength of my LED device is 395 nm (nanometers), up at the high end of the UV spectrum.

Butvar-76 and Glyptal flouresce. Repairs with epoxy and epoxy casts flouresce brightly. Casts made of polyester resin do not flouresce. That is, in the wave-length produced by these LEDs.

 

As I mentioned earlier, epoxy resin flouresces but polyester resin does not. Here is a cast of a bear-dog maxilla made of epoxy resin colored with tempera pigments.

 

 

This is a cast from one of the first molds I made, so don't be too critical of the rendition. But, look at the way the epoxy flouresces in UVA!

 

Examination for authenticity is one of the prime uses for UVA (not to mention checking hand-stamps at your local concert or rave.)

 

I was surprised to find that polyester resin does not flouresce, though epoxy resin does. Among bottle collectors, for example, I would expect optically-clear polyester resin would be the repair material of choice, making UVA examination useless.

 

Body fillers like "Bondo" which use polyester resin as a binder would not flouresce.

 

But another dilemma has arisen. Epoxy repairs are very common in vertebrate fossil preparation. Vertebrate bones are often found in pieces, so patches, extensions, and joins are common. Perfection is appreciated in a vertebrate fossil; but, repairs are the norm, so such restoration does not much affect collector interest. (This is a somewhat different attitude than when dealing with invertebrates.)

 

The dilemma? . . . Some of my best, most esthetic vertebrate fossils look awful under UVA because of the lightning-streaks of expoxy joins and repairs!

Thanks @Harry Pristis. I'll probably get the UV light to check for the rave stamps!

 

Really great info here and very helpful for a newbie. Appreciate you taking the time to comment.