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02-10-2011, 11:51 AM
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Enthusiast
Shorewood, WI
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Join Date: Jun 2004
Posts: 1,855
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Re: Vermilion Test
Wow, thank you Jim, another great feat!!!
I take this to mean my Doak Vermilion is definitely not mercuric sulphide. Good.
-Karen
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02-10-2011, 12:41 PM
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Enthusiast
Broken Arrow, Oklahoma
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Join Date: Jan 2004
Posts: 1,556
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Re: Vermilion Test
Quote:
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Originally Posted by ly
Hi Jim
Thanks a lot.
Now I can safely use Vasari CadVermilion.
Also I will use safely Chrome Yellow from NP(which is coated chrome yellow
that is a lightfast version and may be WN used this type of pigment).
I'm not shure if I can use safely Prusian blue as most tests done by others
shows it is not so lightfast.
Thanks gain
ly
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Ly,
I have tested several Prussian Blues and can say that every single sample (samples from the 1980's, 1990's and 2000's) of Grumbacher Pre-Tested Prussian Blue is absolutely lightfast and would recommend this as a reliable Prussian Blue.
The Chrome yellows I tested were also the coated pigments and were completely lightfast.
__________________
"Extraordinary claims require extraordinary evidence."
-- Carl Sagan
Brian Firth
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02-10-2011, 12:48 PM
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Enthusiast
Broken Arrow, Oklahoma
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Join Date: Jan 2004
Posts: 1,556
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Re: Vermilion Test
Quote:
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Originally Posted by karenlee
Wow, thank you Jim, another great feat!!!
I take this to mean my Doak Vermilion is definitely not mercuric sulphide. Good.
-Karen
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Karen,
But you are paying a premium price for a paint that should be priced the same as other cadmium reds ($40 for the "vermilion" and $22 for cad red). It is sold under the false impression that it is made from a much rarer and expensive pigment, which is the determining factor in pricing paints. Doak's version is called Vermilion Genuine after all, so any reasonable person would assume this to mean it is genuine vermilion! This to me is dishonest and I choose not to do business with businesses that act in this way.
__________________
"Extraordinary claims require extraordinary evidence."
-- Carl Sagan
Brian Firth
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02-10-2011, 01:32 PM
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Member
Israel
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Join Date: Apr 2001
Posts: 87
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Re: Vermilion Test
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Originally Posted by Brian Firth
Ly,
I have tested several Prussian Blues and can say that every single sample (samples from the 1980's, 1990's and 2000's) of Grumbacher Pre-Tested Prussian Blue is absolutely lightfast and would recommend this as a reliable Prussian Blue.
The Chrome yellows I tested were also the coated pigments and were completely lightfast.
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Hi Brian
Thanks for the info.
I have Da Vinci Prussian blue(oil paint), did you test this paint ?
(according to Handprint it is lightfast)
http://www.handprint.com/HP/WCL/waterfs.html
Thanks
ly
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02-10-2011, 02:48 PM
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Member
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Join Date: Jun 2010
Posts: 64
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Re: Vermilion Test
[quote=gunzorro]
Quote:
I've literally "assembled" examples for you to view, in all their redundency, along with an extraneous color bonus (a reward for your patience!). 
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Thanks a million, Jim  I can't say enough on how valuable your work is to us. I appreciate immensily your dedication and research.
Quote:
Obviously, there are (at least) two types of pigment here! The Vasari is the only one listed as PR113, a combination cadmium/mercury pigment. All the others are reported by their makers to be genuine PR106, with the exception of Blue Ridge, who is listing their paint as "cadmium" until such time as it can offer conclusive proof of the pigment.
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Maybe the "manufacturer's" won't tell us what the real pigment is, but I believe the sun has.
Quote:
Beyond these tests, the next step would be scientific analysis of the pigment samples to determine why some are darker than others. I will gladly off these samples if someone wishes to underwrite the cost of testing. Just let me know the lab, and I'll send them the samples. Otherwise, this is the extent of my involvment in the testing and comparison of vermilion pigments. (Whew!)
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Well done.
Tony
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02-10-2011, 02:53 PM
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Member
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Join Date: Jun 2010
Posts: 64
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Re: Vermilion Test
[quote=Brian Firth]J
Quote:
The results are what I expected, the proven real vermillon darkened, while the other "vermilions" (from companies that don't comply with ASTM standards) didn't. There is really no need to test these pigments, any manufacturer of real vermilion paint should easily be able to provide an MSDS sheet from the manufacturer of the genuine vermilion mercuric sulphide PR106 pigment (there's only one or two in the world). Any company that can't is hiding something, it is up to them to prove their product is real, not us the consumer. Real vermilion darkens in sunlight, period. That says it all to me about the other "vermilions".
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02-10-2011, 03:03 PM
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Member
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Join Date: Jun 2010
Posts: 64
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Re: Vermilion Test
[quote=ly]
Quote:
I'm not shure if I can use safely Prusian blue as most tests done by others
shows it is not so lightfast. ly
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Ly,
There is one way to be sure. Paint a strip of your Prussian Blue PB 27 along side others of Ultramarine Blue PB 29, Cobalt Blue PB 28, Cerulean Blue PB 36 etc. and expose them to sunshine for a year or so in your window. Time and the sun will soon answer your questions. 
Tony
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02-10-2011, 06:02 PM
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Enthusiast
Broken Arrow, Oklahoma
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Join Date: Jan 2004
Posts: 1,556
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Re: Vermilion Test
Ly,
No, I haven't tested the Da Vinci Prussian Blue. I have only tested their PY83 in oils, which did very well. From my correspondence with the owner of Da Vinci, Marcello Dworzak, I can say they seem dedicated to producing high quality materials. However, I would second Tony's suggestion of doing your own test. It has been my experience that defective prussian blue pigment fades fast, as in a month or two in tints with white. So, you should be able to quickly determine it's general lighfastness. Of course, I have tested different prussian blues from the same paint manufacturers, like Winsor and Newton, and some were perfectly lightfast and other not leading me to conclude it is an issue of inconsistency from the pigment manufacturers, but that is only speculation. The reality is that no single pigment is constant in its lighfastess. Even bad batches of cadmiums and bismuth vanadate pigments are sometimes seen, as documented on handprint.com's results. Only Grumbacher was consistently lightfast in all samples of prussian blue, but the scope of my tests was very limited and there are many brands I haven't tested.
__________________
"Extraordinary claims require extraordinary evidence."
-- Carl Sagan
Brian Firth
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02-20-2011, 12:46 AM
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A WetCanvas! Patron Saint
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Join Date: May 2000
Posts: 3,707
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Re: Vermilion Test
*
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02-20-2011, 06:38 AM
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Lord of the Arts
East of Eden
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Join Date: Feb 2008
Posts: 2,407
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Re: Vermilion Test
Thanks Gunzorro.
Quote:
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Originally Posted by Brian Firth
Doak's version is called Vermilion Genuine after all, so any reasonable person would assume this to mean it is genuine vermilion! This to me is dishonest and I choose not to do business with businesses that act in this way.
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+1 for me. End of relationship with Doak, before it got started. Good riddance! We've got enough problems with tube labels...
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02-27-2011, 01:59 AM
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A WetCanvas! Patron Saint
Simi Valley, California
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Join Date: Mar 2004
Posts: 3,316
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Re: Vermilion Test
Thanks folks for your support and encouragement. Sorry the tests take so long to accomplish, but I think the results are worthwhile.
I want to thank the manufacturers that contributed samples, particularly Jacques Blockx and Michael Harding (these two being the first to contribute), as well as Studio Products and Blue Ridge. These companies helped make this the most comprehensive display of vermilions and the effects of sunlight that I've ever seen or heard of. Thank you! There is also one benefactor who chose to remain nameless who contributed the NP and RGH samples at his own expense -- thanks! I bought the Vasari and Doak myself.
My results are not intended to foster controversy, and I'm witholding any judgement on the authenticy of the pigments until some day (if ever!) that we can get an chemical analysis to prove the composition.
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01-04-2012, 12:31 AM
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Senior Member
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Join Date: Oct 2010
Posts: 132
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Re: Vermilion Test
Would love to see the results of Jim's test, as the interval has now been long enough to present very instructive results.
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