Home > Hot Button Issues >rageth's speculation masquerades as science
Author:jc
email:
Wed, Aug 17th, 2016 02:07:30 AM
Topic: rageth's speculation masquerades as science

The other day a longtime reader informed us about an online streaming video of a presentation jorg rageth did at the deYoung Museum last year.

It can be seen here:
http://vimeo.com/23979016

RK has mentioned rageth before, and he is surely not an unknown quantity to us.

Fact is we think little of him and his career that has careened from low-end Anatolian kelim dealer to what is alleged by some to be a rug “scholar”.

Far from it is all we have to say.

But our intent here is not to besmirch rageth’s reputation, nor to prove our opinion he is nothing but another rug dealer masquerading as a “scholar” to sell his wares.

Many ruggies probably are familiar with rageth’s representing the ETH laboratory in Zurich, Switzerland C14 (carbon-dating) unit run by Dr. Georges Bonani.

RK has it from reliable sources rageth rounds up the clients, they pay Bonani for C14 testing, and rageth then makes a 30 percent commission on the business he ropes in.

This is rather sleezy and underhanded but typical for the moral fiber that grows in rugDUMB.

The first “project” rageth organized was the C14 testing of a large group of Anatolian Kelim, which resulted in a book published 10 years or so ago.

Our position on C14 dating for non-classsical rugs is also already well known.

For those of you unfamiliar we can sum it up in a few words: We do not believe c14 dating is an accurate tool for accessing the age of any old Anatolian Kelim.

Why?

Plain and simple it’s the contamination issue, read on.

After publishing the C14 and Anatolian Kelim book rageth moved on to Turkmen rugs, and has been threatening for the past half a decade or so of releasing a book detailing C14 dating and other “scientific” findings for these weavings.

So far only talk, no book has appeared.

We doubt it ever will.

The deYoung talk was in rageth’s words a ‘preview’ of this project.

RK doesn't have the energy or desire to critique everything rageth discussed, and we are going to limit this to discussing the central point and focus – the dating of a rare Turkmen supposed ‘eagle-group’ tentband – a detail is pictured below.

In his talk rageth presents a picture that RK has trouble swallowing whole. Though that said we could easily cut out some pieces we’d eat.

Sorry for the metaphor but bear with us here.

This is the chart of the c14 results rageth, Bonani’s star c14 salesman, heralds as a breakthrough.

Frankly, we see it as nothing but pseudo-scientific charade.

Now don’t misunderstand where RK is coming from. We have no, absolutely no, doubt, the tentband in question is very old.

It very well is 300 plus years old. That’s not the issue here.

The issue is scientific testing to prove that, remember the title of his talk is “From Visual Guesstimate to Scientific Estimate – A Turkmen Tent Band Revisited”

The prima facie piece of evidence rageth presents is this chart, the results of the ETH lab C14 test.

Let’s look carefully at the numbers:

AD1520 – 1602 44.4%
AD 1622 – 1674 49.5 %
AD 1786 – 1803 6.1%

What happened to the 20 years between the first two datings, and the 112 years between the second and third one?

We’re sure rageth, Bonani and other proponents have good arguments to explain their absence but logically these omissions doesn’t fly for RK.

Besides the missing decades any percent short of 100% is not science, it is nothing but opinion/guesswork cloaked in faith in numbers.

Sorry, RK has faith in science, and faith in our opinions, but no faith in scientific guesswork and number play.

Again, we think the tentband is that old, we just do not credence this type of short of 100 percent “science” to prove that.

The chart is the lynchpin of rageth’s talk.

He then backs its conclusion with two additional testing procedures SEM (scanning electron microscopy)/EDX (Energy-dispersive X-ray spectroscopy) and Element Mordant Analysis (EMA).

These two procedures, unlike C14 analysis, are real science for Turkmen, or any rug, studies.

They are able give 100 percent true results when properly applied and executed whether on old carpets or any other material.

C14 on the other hand when used for carpets has a major obstacle to reliability – it is called removal of contamination.

And all genuinely old non-classical carpets are far more contaminated than classical ones, which is why C14 dating of that group is more accurate and believable.

But no old rug, be it classical or non-classical, has ever to our knowledge returned a 100 percent percentage for an C14 date.

There are always at least two, and the spread of years between them is surely not easily dismissed, except by true believers like rageth and others, who use the early dates as ‘sales tools’ to convince buyers.

RK has discussed at length these weak links for any carpet dated by c14 and need not revisit them again.

But we will just mention the fact there are a number of different protocol to do the decontamination, and presently different c14 labs use different procedures, as no one has developed a proven 100 percent universal and sure one.

This is why we do not, and neither should you, believe 14 dating of carpets is reliable science, it is not.

If the rug is contaminated the results can be contaminated. Period. End of story.

But we are not going to bicker about that or the missing years in the C14 chart rageth presents.

Rather we would like to poke a few obvious holes in the conclusions rageth draws from the SEM//EDX and EMA results.

In his presentation rageth explains the SEM/EDX test proved the use of Mexican cochineal as the source of the band’s unusually bright and luminous red (the arrow in the picture of the tentband above points to that color).

This is good science, but his conclusions go downhill from there.

According to rageth, based on the research of others, Mexican cochineal came to Spain no earlier than circa 1520, and was probably not available in Central Asia until circa 1550AD.

We have no quibble with this logic but we do with rageth then “narrowing” the dating of the tentband to 1570 – 1670 based on the “tin mordant factor”.

To do this “narrowing” he cites Dutchman Cornelius Jacobszoon Drebbel’s, circa 1610, accidental invention/discovery of using a tin mordant with the cochineal to achieve the unusually bright and luminous red seen in the tentband.

By the way Drebbel was quite the inventor and is credited with devising the first submarine, among other interesting inventions.

This, Drebbel’s tin mordant discovery, is the “scientific evidence” rageth presents for “narrowing the dating window to 1610-1670”.

Here rageth again is presenting opinion as science because this fact only sets-up a valid terminus a quo, ie tin mordant cochineal could not be found in any textile made before 1610.

However, it surely can be found in ones made after that date, and what proof does rageth present that this is not the case with the tentband?

Answer is none.

Let’s be clear here, and again restate we believe the tentband is that old – we just don't credence the supposed “science” rageth advertises as scientific “proof”.

Also: Isn’t it possible some enterprising and brilliant Turkmen, Persian, Anatolian or Jewish dye specialist discovered the process of mordanting cochineal with tin before Cornelius Drebbel did? And therefore the tentband could be even older than the “narrowed” range?

The answer of course is, yes, it is possible, which together with the points above establish a major sink-hole in the “scientific evidence” rageth uses to “narrow the dating of the tentband to 1610 – 1670AD”.

Science is not opinion or conjecture, it must be like math 2 plus 2 equal four.

Unfortunately for rageth and his supporters c14 dating for old carpets and weavings is speculation and while it might look good on paper in reality rageth’s talk, or his publication on c14 dating Anatolian Kelim, falls far short of reliable science.

Finding the tin mordant is science but all the rest of his talk is nothing but, as we wrote about, pseudo-scientific charade.

Author: jc
email:
Wed, Aug 17th, 2016 02:07:30 AM

Just a short comment to point out how blustery brave hearts like Steve Seeman assail RK for supposed misdeeds but then when confronted with the facts disappear like ink on a cheap t-shirt in a hot wash.

Author: Steve Seeman
email: steveseeman@charter.net
Tue, Aug 9th, 2016 02:03:13 AM

RK Replies: Hi there Steve, and welcome to RugKazbah.com

First off it is interesting you chose to air your distaste for RK's comments about jurg rageth and his recent Turkmen carpet publication in this quite old thread rather than any of the far more recent threads which discuss rageth's book in detail.

Might RK ask why?

Now then, Steve, concerning the major issue in rageth's text RK took exception to -- the issue of contamination of samples and the effects of this contamination on the results of c14 analysis -- your claim rageth and Bonani explained this issue is far from sufficient to discount it.

This book rests it case on the c14 analysis of contaminated Turkmen weavings, a situation which is at best flawed and at the worst negates any real meaning it might bring to Turkmen studies.

As for the alleged explanations you claim rageth and Bonani offered?

Actually all they have done is repeat the same insufficient chant they uttered in rageth and Bonani's Anatolian Kilim publication, which likewise presented c14 dates that are highly suspect. Again on account of the contamination issue.

As for the other important issue -- rageth's at best sophomoric knowlerdge about historic Turkmen weavings -- one we are sure to be a statement you would consider "bullying", we defy you or anyone else to offer real and genuine argument to the contrary.

It is obvious name calling, like referring to RK as a bully, is far easier than proving someone is wrong. Remember we did not use any ad hominem attacks on rageth. We proved, not accused.

As our final comment, but we could go on, rageth's book is poorly organized, designed and conceived. Reading it is a tedious exercise and the color printing is less than brilliant, far less. It is not an art book, and neither it is a scholarly text book.

The amateurish production mirrors the often amateurish ideas and conclusion rageth writes.

We are sending you an email to personally invite you to try and prove any of RK's extensive commentary on rageth's book wrong here on RugKazbah.com.

Do not forget your seeing 'value' in rageth's book is alot different than proving where that 'value' supposedly is.

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The author of this article seems to rant, rave, and bully based on an insufficient knowledge of science. It would behoove the author to read and understand (?) the section in Volume 1 of Jurg Rageth's new book (...A new Perspective) by Bonani and Rageth on "Dating Turkmen Weavings". This section explains how the dating probabilities are determined (by shape of accepted calibration curves), and the detailed methods used to lower the effects of contamination on the tested samples.

After reading other critiques by the author I see that convincing him/her of the validity and value of Rageth's book may be an exercise in futility; self-adsorbed bullies rarely can be convinced they are wrong.

I encourage others to review Jurg's book and draw their own conclusions.

Author: jc
email:
Mon, Sep 21st, 2015 07:06:14 AM

In the hyperbolic world of oriental rug collecting nothing shines brighter than Ebberhart Hermann's supposed forthcoming treatise that among other self-proclaimed achievements will demonstrate the origins and sources of all art, not only oriental rugs.

But while a second far less imposing or all encompassing publication on Turkmen weaving by jorg rageth has been equally self-hyped for at least as long, and we are talking about almost a decade, it too for all intents and purposes appears to be equally as stuck in the mud.

RK finds this situation comical and although Hermann's project's hang-up is much more easily explained -- first off he's a bit touched and second who could possibly explain in one work where all art comes from? -- ragth's pathetic excuses and now stale as last week's toast claims "I am working on the introduction, everything else is finished, and it will be published this year" make even less sense.

RK sincerely believes this Hermann book will never see the light of day.

As for rageth's book? We do believe it will eventually appear. And while it is impossible to judge a book by its cover, particularly an unseen one, let RK prognosticate just like his other book on c14 dating of Anatolian Kelim this one too will be flawed and eminently critiquable.

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