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I would like to melt some amber to make amber varnish.  I'm using Violin Varnish and How To Make It as a reference.  The text says to heat amber in an earthenware vessel and pour it onto a marble slab.  After it has cooled, you are supposed to grind it into a powder, mix it with either linseed oil or turpentine and it will dissolve under low heat.  I have some questions about this.  Could white Corningware be used as the vessel?  Other texts I have referenced say use and iron pot. Which is best?  Nothing I have read talks about using a cover but I am thinking a cover would help prevent oxygen from entering the melt.  Should I use a cover?  Some texts talk about using some siccative oil or turpentine in the melting process.  I'm worried about hitting the self ignition point of the solvent if I do this.  Is this advisable?  Any and all advice would be greatly appreciated!  I do realize this this is an outdoor activity to be accompanied by a fire extinguisher.   Thanks in advance, Dan.

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I've never tried it yet myself, but amber requires very high temperatures to melt. Because of the elevated temperatures involved, any turpentine added to the mixture will likely set the resin on fire because the heat is far beyond the flashpoint of turpentine.

 

A stainless pot might be a better choice over the corning ware, or an iron pot. Keep in mind that much of the material is lost during the cooking process, at least half of the amber. I would seriously consider using an induction cook top to eliminate any open flame.

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I've never tried it yet myself, but amber requires very high temperatures to melt.

 

I too have never tried it, but I did watch somebody "melting" amber.  I'm not so sure the amber melted as much as it decomposed into something else, more like asphalt.  It smelled like a freshly graded road or hot-mopped roof.  I remember his wooden stirring stick would occasionally catch on fire, and he'd have to blow it out, and the process was carried out over a gas-fired cooktop (outdoors, at least).

 

It didn't seem like something I'd want to try.

 

However, if someone has found a successful method of getting amber relatively intact into an oil varnish, I might be interested.

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Two more books that are possibly worth reading prior to making an amber varnish are:

1. "Classic Italian Violin Varnish" by Geary Baese

2. "Violin Varnish and Coloration" by Martins Roberts Zemitis

 

I've made a number of amber varnishes over the years and there are a few points that are worth noting:

1.  The temperature required to successfully run amber is somewhat higher than those necessary to create Pinaceae resin varnishes.  As a consequence the danger element is increased. 

2.  Heat energy also seems to be important; i.e., you need enough heat energy to quickly break down the amber and get it to run.  If you don't have enough heat energy you end up with what Don has described.

3.  An iron pot does work but I have never been sure to what extent iron gets introduced into the mix.  A stainless steel vessel/pot, which also works, is possibly better if this is of concern to you.  For my most recent batches I have used small ceramic pots.  While these pots have worked well, you need to be very aware of potential thermal shock issues.  Stainless steel/iron is better in this regard.

4.  I always use a sand bath to avoid hot spots and localised burning of the resin.

5.  Do not use a lid/cover on the pot.  Others may disagree but I have found that this creates a situation that is much more likely to result in trapped volatiles and then the amber catching fire...  Such a fire is to be avoided.  (Trust me on this!!!)

6.  Always make these varnishes outside, well away from anything that can catch fire.

7.  Avoid breathing the fumes.  Running amber results in significant fuming and a very strong smell.  Your neighbours will very quickly become very aware of your cooking efforts. 

 

Amber varnishes can look very nice but it is important to run but not burn the amber.  Burning/over cooking tends to result in a colder looking varnish.

 

Good luck and be careful!

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Two more books that are possibly worth reading prior to making an amber varnish are:

1. "Classic Italian Violin Varnish" by Geary Baese

2. "Violin Varnish and Coloration" by Martins Roberts Zemitis

 

I've made a number of amber varnishes over the years and there are a few points that are worth noting:

1.  The temperature required to successfully run amber is somewhat higher than those necessary to create Pinaceae resin varnishes.  As a consequence the danger element is increased. 

2.  Heat energy also seems to be important; i.e., you need enough heat energy to quickly break down the amber and get it to run.  If you don't have enough heat energy you end up with what Don has described.

3.  An iron pot does work but I have never been sure to what extent iron gets introduced into the mix.  A stainless steel vessel/pot, which also works, is possibly better if this is of concern to you.  For my most recent batches I have used small ceramic pots.  While these pots have worked well, you need to be very aware of potential thermal shock issues.  Stainless steel/iron is better in this regard.

4.  I always use a sand bath to avoid hot spots and localised burning of the resin.

5.  Do not use a lid/cover on the pot.  Others may disagree but I have found that this creates a situation that is much more likely to result in trapped volatiles and then the amber catching fire...  Such a fire is to be avoided.  (Trust me on this!!!)

6.  Always make these varnishes outside, well away from anything that can catch fire.

7.  Avoid breathing the fumes.  Running amber results in significant fuming and a very strong smell.  Your neighbours will very quickly become very aware of your cooking efforts. 

 

Amber varnishes can look very nice but it is important to run but not burn the amber.  Burning/over cooking tends to result in a colder looking varnish.

 

Good luck and be careful!

Thank you John. Great info.

Question: Why do some prefer amber varnish over a pine resin varnish?

I have found amber varnishes much more difficult to rub out and in between coats plus I find a lot more dust attraction to amber varnish than pine.

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I guess it's nice to start at the top and work down.  I've made enough fossil copal varnishes I think I can make them in my sleep, but it would think twice about amber, a notch more difficult. I've attached something on types of amber, in another part of this paper it considers amber varnish the finest, but that doesn't mean for insts. I'm curious to know why.

Even though I've not cooked amber, it seems to be similar to fossil copal, which means being able to maintain temp's around 620-630F. For initial runs, to overcome the starting melt of the amber, add around 10-15% rosin, this lo temp melt will keep the amber from trying to climb out of your cooker.  Also you need a jacket to  heat the walls of the container, otherwise you will not be able to keep the amber in contact with the bottom. If you are using a hot plate, place a piece of aluminum over the burner, a cut down to about an inche a can a little wider than the cooking container  with a little sand in it to distribute entering heat. You then place another can from the hot plate to near the top of  the  cooking container, having an air space about 1/4 inch between container and jacket. This is to keep the walls hot so the amber can't crawl up and stick there. Stirring stick to push down amber- keep it cold so as to not stick to amber, and if it seem like it will stick, stop using it. You know you've overcome step one when it quietly  goes up and down near the bottom, and when you get the first bubble coming out from the bottom you've got it licked. Keep increasing heat slowly, bubbles increase, more rapid moving,, getting smaller in size. Hopefully if you don't have a thermometer that surface foam is present. If it is, keep it almost equal to the original volume at the start of the cook. You know the cook is done when it sinks back to its original volume and it looks like it is just quietly vibrating (it is actually boiling but you can't see it).  Shut off heat to cool and to add hot ail.  I hope you are able to make it, I hope this sketchy info helps.

 

post-24779-0-06522700-1419734807_thumb.jpg

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I have the Baese book(s) and I find them unhelpful--pretty much all books are unhelpful here. Making amber varnish is definitely a skill I wish I had just by reading the books. Baese used the de Mayerne/Sloane manuscript that the Fels book deals with, and you don't have to sign a waiver of secrecy to read the Fels book.

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The large amount of amber I have is probably best kept in chunks, because they might be valuable. I've tried. Seeing the amber run is exhilarating but that quickly becomes a feeling of dread and failure. The amber asphalt chunk that turns into dust, which Don described, is particularly depressing. It happens fast...the good liquid amber is already burned and gummy by the time I'm transferring it to marble, and when it's cool it's sparkling carbon.

Pretty much any other resin would be easier. A member here generously sent some other varnish materials, which I am sure I will be able to turn into something better than the amber became. I made an orange alizarin color wash to be applied over the mostly untreated wood, and tried throwing some dust in that, and another time I didn't have turpentine to make the wash again so I rubbed the amber asphalt stuff mixed with tamanu oil into my skin. It's good for that...if anyone cares...but what a waste of a hundred million years.

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  Some texts talk about using some siccative oil or turpentine in the melting process.  

 

I have not yet made Amber varnish, should be making some soon for 2  bloodwood/imbuia/scagliola tables I am in the process of making, the turpentine (sap - not spirits of turpentine) as I understand brings down the fuse point of amber (or other hard resins) and aids in the fusion in a lower temperature, not all saps are equal, it also makes the varnish not as hard (lower fuse point of resins).

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Wow!  I don't know what to say!  I am very grateful for all the information and the time it took for you folks to post it.  It looks like this may be more difficult than I anticipated but I will try it this spring (when it gets warm enough outside).  I have the amber which is in the form of very small pebbles so it's not worth much as a specimen.  Actually, I'm sort of looking forward to a melting pyre of pyroclastic material giving off noxious fumes.  Reminds me of my early days as a chemistry student! 

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Adding another material to bring down the melting point is a fantastic idea!  Would pine rosin work?  I've done some work in metals and, with metal alloys, the melting point of the alloy is always lower than the lowest melting point of any metal used in the alloy.  It sounds like a similar principle here.

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Question: Why do some prefer amber varnish over a pine resin varnish?

I have found amber varnishes much more difficult to rub out and in between coats plus I find a lot more dust attraction to amber varnish than pine.

 

Hi Ernie,

 

I've found that amber varnish can look okay in the context of an initial varnish application, in my case sometimes very slightly nicer than Pinaceae resin varnishes that I've made.  It also seems that amber may have interesting acoustic properties (As reported by Martin Schleske).
 
I haven't used amber varnish for anything other than an initial coating so I can't really comment about how it rubs out but can imagine that there could be a dust attraction issue.
 
John
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Would a lid to a pot be a handy thing to have around if the amber cook sets on fire?

 

Cooking is an art and not everyone can do it equally well.  Just ask Gordon Ramsey of Hell's Kitchen fame.

So for a first time event, I would start by purchasing Amber varnish first, so you will know what your final goal should look like.

Then you can test it on a piece of sample wood, and compare to store bought.

 

When it was pointed out that Amber has a high melting point, I checked it out on the Web.

 

"Physical characteristics

 

Many components of amber are similar to those of modern resins. However the cross-linking of these compounds makes the amber hard, with a high melting point and low solubility. Amber has a hardness of 2-3 on Mohs's scale, the standard for minerals and gems. On this scale, talc is I and diamond is 10. Amber softens at 302°F (150°C) and melts at 482-662°F (250-350°C). With a specific gravity of 1.05-1.12, amber is only slightly more dense than water. It will not completely dissolve in organic solvents.

Amber usually occurs as small irregular masses, nodules, or droplets. Although it can be many different colors, it is most often pale to golden yellow or orange and can be fluorescent. After a few years of exposure to light and air, amber often turns dark red and develops numerous cracks on the surface. Some amber is translucent or even transparent. However, trapped air bubbles can cause amber to be cloudy or opaque. Amber is a poor conductor of heat and large changes in temperature can cause it to fracture."

 
So because the melting range is so varied, 482-662°F (250-350°C), then it means Amber itself varies.  That running a small batch of unknown Amber is a hard task to do successfully.  Experience is needed.   You can't just heat up your resin to a certain number.
 
About cooking the varnish.
Would it not be best to cook it in winter, if you have neighbors that will smell it?
Spring time sees windows opened.
 
 
My Chemistry is rudimental, so I could be wrong, but alloyed metals have already been heated to their melting temperatures before being combined, so it is only the comined/alloyed metal that has a lower melting point.
 
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The best amber varnish I have used is made by Donald Fels of the Netherlands. He told me he knew Koen Padding and in fact showed him how he made his amber varnish.

If I want to use amber vanish then I will buy his.

http://www.alchemistmediums.com/

I see that they also offer this book.

 

http://www.alchemistmediums.com/index.php?pr=products_book

 

"Lost Secrets of Flemish Painting"

 

Amber certainly looks very interesting, and may be the Lost Secret of Stradivari.

Downside is that it seems to be the hardest varnish to cook, and high temperatures look dangerous.

Maybe that is why it was abandoned after Stradivari?

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I will  definitely follow your advice on buying amber varnish first.  As far as not doing it now, I live in Nebraska.  The forecast high for tomorrow is 9 degrees F.  I live on a small farm and my nearest neighbor is about a half mile away so bothering neighbors is not an issue.  The information you provided is great!  I had done some research but this is the best I've read.  Thanks for taking the time to do it.  Dan.

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Adding another material to bring down the melting point is a fantastic idea!  Would pine rosin work?  I've done some work in metals and, with metal alloys, the melting point of the alloy is always lower than the lowest melting point of any metal used in the alloy.  It sounds like a similar principle here.

 

In spite of recipes advocating adding the likes of colophony to amber, I haven't had success using this approach.  The end result has been as Don described...  The colophony pretty much broke down/carbonised before the amber started to melt/run.  If anything, it seemed to hinder the amber starting to melt.  (This may have been due to the colophony being a less than ideal particle size; i.e., powdered.  I would need to go back to my notes and check what I did use/do...)

 

It seems that the size of the amber pieces is significant.  While you don't want huge chucks of amber in the pot, crushing amber into very small pieces/powder hasn't worked for me.  Powdered amber seems to just sweat and then carbonise.  (Maybe my heat source was too strong in this particular instance????  I don't know... )

 

Running amber is a bit of a mission.  There do seem to be differences between various colours of amber and the temperatures required to get them to run.  I used to be preoccupied with thermometer readings but now just crank up the heat and watch carefully.  I do have a thermometer immersed in the sand bath but this is only a vague guide.  Once the temperature is getting up towards 350°C, things start to happen and it seems that it's important to get the temperature up there reasonably quickly.  Once the amber has started to run I remove the thermometer and pull back the heat input, noting the types of behaviour that Fred has mentioned  This has been the only way in which I have been able to consistently and successfully run amber...  (Note that immersion depths for each thermometer and where the thermometer bulb may be sitting in relation to the bottom of the pot containing the resin will only ever result in a very approximate indication of what may exist inside the resin pot.)

 

John

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I see that they also offer this book.

 

http://www.alchemistmediums.com/index.php?pr=products_book

 

"Lost Secrets of Flemish Painting"

 

Amber certainly looks very interesting, and may be the Lost Secret of Stradivari.

Downside is that it seems to be the hardest varnish to cook, and high temperatures look dangerous.

Maybe that is why it was abandoned after Stradivari?

 

This is an interesting and useful book and should have been included in my list in post #5. 

 

Could copal varnishes have replaced the use of amber varnishes?

Fred, do you know when the wide spread use of copal varnish became the norm?

 

Amber is notoriously difficult to detect in varnish films, making it almost impossible to tell with certainty when and where it may have featured.  (It transpires that copal is also very difficult to detect in varnish films, much more so than researchers previously envisaged...)

 

John

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Would a lid to a pot be a handy thing to have around if the amber cook sets on fire?

 
About cooking the varnish.
Would it not be best to cook it in winter, if you have neighbors that will smell it?
Spring time sees windows opened.

 

 

A lid may work.  However I'm not sure whether trapping burning volatiles within an enclosed space is a good idea.  I would guess that lack of oxygen would quickly take effect but, until then, could the situation become even more dangerous?

From memory I quickly removed the sand bath pot containing the resin pot from the heat source and then carefully poured sand into the resin pot.  (My sand bath pot has a long handle that is easy to grab.  I also have heat/fire proof gloves handy, but have never had to use those...  yet....) 

 

I do my varnish cooking in summer.  The higher ambient air temperatures seem to help.  Any running of amber is done during week days when everyone is away at work and hopefully no washing is out on clothes lines...    :^)

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I would say that fusing amber is only different from fusing pine resin in that you need a somewhat higher temperature in your pot.  I like amber varnish for lower coats and dislike it for upper coats.   There is something optical about it that is pleasing when it is down low and near the wood.  You should definitely grind the raw amber well to a fine dust in a   coffee grinder  before you begin your fuse and I use cheap porcelain pots you can get at Walmart or some such store.    The ones with the old fashioned speckled surface. Without checking  my notes, you need a temp over 300 Celsius.  Run it for a couple of hours on a hot electric burner, cool it, and then regrind it before adding it to hot oil.  Pretty simple.  All the fuse about fusing amber came from the use of open flames, I suspect.  

 

Be careful...wear long sleeves, gloves, and eye protection.

 

Good luck,

 

Kelvin 

 

 

 

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Could copal varnishes have replaced the use of amber varnishes?

Fred, do you know when the wide spread use of copal varnish became the norm?

 

I'm not Fred, but I'll throw in a bit of info, in late 1600's and early 1700's Italian literature there are a lot of Copal recipes, and lots of raves about this specific resin, which was according to mentioned literature a white, sometimes a little yellow, shining and very pale resin which drops from a tree in north and south America, called "iatai" by the indians of Paraguay. According to a 1700's source.

 

When the Copal resin is collected amongst the roots and trunk of the Iatai tree, itʼs white and transparent, while still not mixed with dust or soil, with time, nonetheless it gets dirty, and yellows a bit, little by little. When it is transparent and light colored it is splendid for Varnish, but hardly dissolves with spirit of wine.

 

Copal (indian name) is the resin which today is called Mesoamerican Copal, or White Mayan Copal or White Mexican Copal, not the other hard resins, these at a certain time borrowed the name, and a huge mess in varnish literature begun, even Copaiba Oleoresin has been called Copal in old literature....

 

I often wonder if the hard Copals where not sold as Carabe, or Amber and the recipes are the same. ???

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