Forensic Chemistry

[bombsaway]

That's fine Bombsaway and I will stop grilling you over it now, because that's about as far as we can take your hypothesis. It requires very specific parameters as we explored, and it needs those parameters to be configured exactly as you need them, with no variation possible.

So again, these very specific parameters that I have configured are

gas chambers in majdanek weren't cleaned after the evidenced delousing runs were done

gas chambers in Auschwitz were evidenced to have been cleaned after use (and logically this makes sense), no known use as delousing chambers

Did you just forget your own hypothesis? The theoretical cleaning agents being applied after a homicidal gassing to remove the urine and feces. Not a delousing. This is what you need to have been interrupted at Majdanek at least once* for your model to work, allowing a sequence break where the bleach was absent to allow PB formation during any subsequent HcN exposure.

*When I say at least once I'm being VERY generous because the PB formation is very visible, and is likely an accumulation of every instance of exposure of HcN. In reality, you need your "unbroken cleaning sequence" to have broken every time Zyklon was deployed in Majdanek and zero times in Birkenau.

Do you get it now that you are threading the eye of a needle?

No, I am just following what the AI said, which was that the cleanings had to be regular. A single cleaning isn't going to inhibit for weeks or months.

[Nessie]

No so-called revisionist can deal with the point that the Majdanek delousing/gas chamber, does not have a uniform spread of Prussian blue. If it was blown up and partially collapsed, it would be possible for an accessible part to not show any obvious staining. If it was completely demolished, no one would know anything about how stained its walls were.

For all you lot know, there was Prussian blue staining on the walls of Kremas II to V and the two bunker farm houses. But, since it was not uniformly spread, it appears to not be in Krema II and with demolitions, the rest cannot be viewed at all.

Only Krema I is intact, but, what was done to the walls, after 1943, when it stopped being used for gassings? How much, if any, Prussian blue was visible, even in small amounts, in 1943? We do not know.

Just because your lot cannot work out, to your satisfaction, why there is no obviously Prussian blue staining, at the A-B gas chambers, does not therefore mean none was used for gassings.

[ConfusedJew]

When we review the material, both concrete and lime mortar are more porous than brick, not less. Which is the opposite to what you are arguing.

Likewise the diffusion properties of various building materials are known, and both lime plaster and concrete have higher diffusion co-efficients than brick when compared:



All of this builds us a compelling picture that the environment of the homicidial gas chambers is even more hospitable to PB formation than the delousing chambers on every metric you can possibly conjure.

I didn't mention porosity or diffusion. My research suggests that the homicidal chambers did not have enough reactive iron to form Prussian Blue.

How do you argue that those properties make the environment "more hospitable to PB formation than the delousing chambers on every metric you can possibly conjure"? This doesn't make sense to me personally and I don't think that it makes logical sense at all.

In theory, concrete and lime could absorb more HCN than brick surfaces but more porous does not mean that there will be Prussian Blue. Porosity, absorption, and diffusion aren’t the limiting factor for Prussian Blue formation. The chemical reaction pathway is.

[Archie]

Regarding the pH, for context, this is the part I was remembering from Rudolf.

As an example for Green’s arrogant ignorance I want to address the question of the pH value of masonry. I agree with him that an alkaline environment is a basic requirement, so that hydrogen cyanide dissolved in water, which is
always present in the micropores of the masonry, is converted into soluble cyanide salts. This is the first step toward the later conversion into the long-term stable Iron Blue pigment. In this regard, Green has drawn graphs similar to
mine. He then hypothesizes that masonry is actually pH-neutral or even slightly acidic, so that no accumulation of cyanides can be expected. One does not find any references to scientific literature in his paper backing up his hypothesis. I then pointed out to him, with reference to expert literature on construction material, that his hypothesis is wrong. The fact is that newly erected masonry based on mortar, cement or concrete is always alkaline. This is particularly true for the material used to build the morgues under discussion, which remained alkaline for months, if not years. To this, Green simply stated:

“The IFRC [Institute for Forensic Research, Cracow = Jan Sehn Institute],
on the other hand measured [in 1993] the pH [of mortar samples from the
alleged homicidal gas chambers] to be between 6 and 7 [that is neutral or
slightly acid].”

Instead of consulting expert literature, Dr. Green asked for advice from the researchers of the Jan Sehn Institute? The problem with the value determined by the Jan Sehn Institute is that it was measured 50 years after said walls were
built. If Dr. Green had only the slightest idea about the chemistry of masonry material, he would know that mortars and concrete do of course not stay alkaline eternally. If he would have read or understood my expert report thorough
ly, he would have noticed that I even quoted a PhD thesis to this effect. This thesis determined in the 1960s the speed with which the front of carbonatization (= front of neutralization) progresses into samples of mortar and con
crete. (HH #18, pg. 79)

I asked Grok and it, like GPT, says slightly acidic to neutral pH is favored.

pH and Redox Conditions: The reaction favors slightly acidic to neutral pH environments. Highly alkaline conditions (e.g., in fresh lime plaster, pH ~12–13) can inhibit the formation of Prussian blue by stabilizing cyanide as CN⁻ or forming other compounds. Oxidizing or reducing conditions also affect the iron’s oxidation state, influencing the reaction pathway.

It seems Germar says something similar about very high pH, but he does not agree about the slightly acidic thing. There's seems to be something the AI is missing.

This is from Germar's summary

Increased iron reactivity with falling pH, as well as a massive reduction in cyanide accumulation and redox reactivity of iron(III) cyanide; compromise between iron reactivity and cyanide formation/Fe3+ reduction: A weakly alkaline pH value is favorable to absorption of hydrogen cyanide and accumulation of cyanide as well as for the
reduction in iron(III) cyanide, which determines the velocity of the reaction. Although more-strongly alkaline media can accumulate iron(II) cyanide over longer periods of time, no Iron Blue can form under such circumstances. An extremely high pH value fixates iron(III) as hydroxide and hence impedes the formation of any iron cyanides. (pg. 202)

There is some nuance it seems about how how the cyanide accumulates.

Even in an alkaline environment, it must be expected that rust, in the presence of perceptible cyanide concentrations, will be quite slowly transformed into iron(III) cyanide and finally into iron(II) cyanide. The last step required for the formation of Iron Blue, however, the combination of iron(II) cyanide with iron(III), will not occur due to the lack of dissolved iron(III) ions. In a strongly alkaline environment, an increasing concentration of iron(II) cyanide, which is chemically stable, can slowly accumulate. It might be said to remain in a stand-by position, pending a drop in the pH value.

Iron salts generally tend to incorporate water, and Iron Blue is no exception to this. A higher water content in the solid body results in increased water accumulation in rust, too. The rust swells up, so to speak, which makes it easier for cyanide ions and other ligands to replace the OH– ions around the iron ion. Freshly precipitated, extremely moist and non-homogenous iron hydroxide is very reactive, and together with hydrogen cyanide, as mentioned in Paragraph 6.5.2.2, they form the pigment in visible quantities in minutes. (pg. 194)

[Archie]

Here is what Grok says when I ask it to reconcile.

For walls with available iron (e.g., rust), a weakly alkaline pH (around 7.5–9.31) would be most favorable for Prussian blue accumulation during HCN fumigation. This pH allows:
Adequate CN⁻ formation from HCN dissociation.
Sufficient iron reactivity without significant hydroxide precipitation.
Support for the reduction of Fe³⁺ to Fe²⁺, driving the reaction forward.

In contrast, acidic pH (below 7) would enhance iron reactivity but limit CN⁻ accumulation, while highly alkaline pH (above 10) would block the reaction by fixating iron as hydroxide, even if CN⁻ is present.

[TlsMS93]

“For all you know, there was Prussian blue staining on the walls of Kremas II to V and the two bunker farmhouses”.

I'm curious to know more about this; it's news to me. Show me the photos of the bunkers with their Prussian blue stains.

[Stubble]

I didn't mention porosity or diffusion. My research suggests that the homicidal chambers did not have enough reactive iron to form Prussian Blue.

Based off of your research, can you articulate what 'special' materials were used in the construction of the LK's that somehow had reduced or no iron in them?

Was there a special screening process or order implemented to audit these materials before installation? If so, why?

Given that the bricks used to construct the morgues are identical to other bricks at Auschwitz Birkenau, I find the claim highly dubious that they were screened for iron content and specially selected, personally.

Given that the other concrete and plaster used at Auschwitz Birkenau formed iron blue, I have some apprehension accepting that these materials that were used at Kremas II and III were so screened.

Perhaps you can make clear what led you to assume the iron was removed somehow from the building materials used at the Kremas.

[ConfusedJew]

I didn't say anything like that and you are not understanding what I actually did say. I will reserve my responses for HansHill.

But to be clear, chemically reactive iron (necessary for the formation of PB) is not generic iron.

Forensic studies showed that the plaster in LK1 had very low permeability. The concrete/mortar used in the gas chambers likely had lower free iron content compared to the old red bricks used in delousing chambers. The materials in gas chambers were similar, but not identical, to those used elsewhere in the camp.

Iron in materials typically exists as iron oxides (Fe₂O₃, Fe₃O₄, FeO) – stable, oxidized forms (like rust), bound in silicates (within sand or aggregate), traces of Fe in cement clinker minerals. These aren’t very reactive with cyanide under normal conditions. What’s needed to form Prussian blue is free Fe³⁺ ions — that is, iron soluble in water and capable of bonding with cyanide ions.

Most iron in concrete or plaster is tightly bound in mineral lattices, does not dissolve in water easily, is not available in ionic form (Fe³⁺ or Fe²⁺). In other words it was there, just chemically unavailable for forming Prussian blue.

In Leichenkeller 1, the surfaces were plastered and smoothed, sometimes whitewashed. Whitewashing adds lime (Ca(OH)₂), increasing pH even more. The gas chambers were cold, damp, and not continuously exposed.

These factors combine to seal the surface, prevent deep penetration of HCN, and minimize moisture + air exchange, which is needed to generate soluble iron ions.

[ConfusedJew]

Regarding the porosity of the surfaces in LK1:

Rudolf assumed that plaster and concrete are porous enough to behave like brick — but this is only partially true, and misleading in context. While microporosity exists in concrete and plaster, that doesn't mean gas can freely penetrate the material. Plastered walls in the gas chambers were finished, whitewashed, and often smoothed/sealed, reducing surface permeability. Rudolf didn't account for the effects of lime-based whitewash, which forms an impermeable crystalline layer.

Rudolf argued that if cyanide touched iron-containing material, Prussian blue must form. But in reality, iron must be in the Fe³⁺ form. Rudolf's mistake was that he did not address or test what inhibits Prussian blue formation, he only tested what promotes it.

[Stubble]

So, you are saying that the delousing chambers used a different plaster?



This whole argument from you seems to be 'special pleading'.

The reason that I said the material would have had to have been screened to remove iron, is because, the reactive iron, is obviously present otherwise.

/shrug

I'll go ahead and let Mr Hill take it from here though, apparently I haven't been clear enough for you, although, if we are being honest, I don't have any idea how to be more clear.

[ConfusedJew]

I might be wrong about some things here but this is what I'm seeing.

The wall material in the homicidal gas chambers was similar in basic construction material (brick or concrete), but not always identical in surface composition (e.g. plaster type, iron content, porosity), and the conditions of use were very different, which significantly affected chemical reactions like the formation of Prussian blue.

[Wetzelrad]

Allow me to demonstrate once again that ConfusedJew is relying on AI hallucinations to write his posts. Summary at bottom.

The Zyklon B was released gas quickly enough in warm, enclosed chambers. Zyklon B was chosen specifically because it was effective at killing large numbers of people in a short time. Over time, the Nazis refined the process for "efficiency", including heating the chambers or pre-warming the Zyklon to accelerate gas release.

The idea that gas chambers were heated arises from documents that Jean-Claude Pressac found, however this is speculative on his part. The innocuous explanation for heating a morgue is that it prevents the morgue from freezing in the winter, because contrary to your assertion the morgue in winter was not "warm" but ice cold. As far as I know no witness testifies to heating gas chambers.

There was also no circulation device to "pre-warm the Zyklon". That can be found in some disinfestation chambers. In the homicidal gas chambers they simply dumped the Zyklon on the floor, or so we are told.

Krema I (in Auschwitz I) was the first stationary gas chamber used at Auschwitz and was later converted into a morgue at which point, [...]

It's the opposite. According to the USHMM, the morgue was converted to a gas chamber, then later to an air raid shelter.

[...] many mass killings shifted to Birkenau (Auschwitz II), where Kremas II–V were purpose-built for mass extermination.

Pressac's position is that those crematoria were purpose-built as crematoria, their lower chambers intended as morgues. They were converted to gas chambers. This is a kind of semantic difference, so I won't count it against you.

Krema I had a swinging wooden door, which would not be ideal for pressure sealing but it was retrofitted with latches and possibly rubber seals to improve gas retention.

This is a hallucination. As far as I know no Holocaust believer even concedes that this door was a swinging door because of how contrary that is to the homicidal gassing story. The bit about latches and rubber seals is made up.

The gas chamber only needed to retain gas for 10–20 minutes which did not require hermetic sealing like in modern biohazard labs. Even though it did not use an airtight seal, the swinging door was adequate to do the job.

Ridiculous. If gas passes through what you admit is not an airtight seal, then everyone in the building is getting poisoned. This AI will get people killed claiming it's "only 10-20 minutes" of poison.

Separately, Zyklon B introduction vents are still visible in ruins of Krema II and III.

They aren't, but this is contested so not really an AI error.

Technical details from Auschwitz blueprints among other sources show that the ventilation used forced-air systems that extracted poisoned air after each gassing. Zyklon B introduction shafts were in the roof; after gassing (~10–20 minutes), fans were activated to remove hydrogen cyanide gas. In the final step, airflow was directed through ventilation ducts, with motors and filters to hasten gas dispersal.

I think substantial parts of this are false, but I'm not going to waste time peeling it apart. The bit at the end about "motors and filters to hasten gas dispersal" is a hallucination that doesn't even make sense.

SS engineer Karl Bischoff’s correspondence provides very clear details on the ventilation and referred to Auschwitz as an extermination camp on 2 September 1942.

https://www.jewishvirtuallibrary.org/do ... -auschwitz

Anyone who takes a moment to check this link will see that the only details provided on "ventilation" concern the heating of the morgue mentioned above. It specifically describes how hot air is to be routed from the furnaces down into the morgue, not how air is to be removed from the morgue. Beside that, it is quite devoid of detail, and it wasn't sent by Bischoff but by Jahrling.

Bischoff most certainly did not refer to Auschwitz as an "extermination camp". This is a very obvious failure in reading comprehension. Did you check any of this before clicking post?

Historical documents, blueprints, and eyewitness testimony all describe the method of Zyklon B introduction Kremas II and III.

You will never find a Nazi blueprint that describes, corroborates, or even hints at Zyklon introduction there. Nor will you find a Nazi document like that, unless you count the one that mentions "4 wire-mesh push-in devices" in morgue #2 AKA the undressing room.

The walls were plastered or lime-coated (e.g., with calcium hydroxide), which chemically inhibits Prussian blue formation by reacting with HCN before it reaches the iron and seals the wall surface, preventing hydrogen cyanide from penetrating. Even if some iron was present, the chemical environment in homicidal chambers did not promote stable iron-cyanide bonding over short exposures.

There is no evidence of lime coating. No one has found lime coating or documentation of lime coating. They found concrete, mortar, and plaster.

The plaster would not inhibit Prussian Blue formation, or else there would not be Prussian Blue on the plaster in the disinfestation buildings. This is a speculative argument against reality.

I will also note that if lime coating is an issue in the gas chambers, then that only puts it on the same footing as the disinfestation chambers, which Rudolf says did have a lime paint coating (p.299, 336).

Regarding pH, alkaline plaster reacts with HCN and converts it to non-cyanide compounds before it can form Prussian blue.
Iron must remain in the oxidized Fe³⁺ form, but lime-based coatings shift conditions away from that.

While I'm not a chemist, this reads like nonsense. A cyanide compound can not convert into a non-cyanide compound. Perhaps what you mean to say is that it converts into a different form of cyanide which cannot form Prussian Blue. (Again it must be pointed out that you are arguing against the formation of Prussian Blue where we actually know it to be.)

The gas chambers at Majdanek had different construction materials, including uncoated concrete and brick, and in some cases were less altered over time. These conditions made chemical reactions more likely to leave blue residue — particularly in delousing chambers, where exposure was extensive.

The gas chambers at Auschwitz are uncoated concrete and plaster, the same as at Majdanek.

"Less altered over time" has no basis. What is the evidence for alteration over time?

The Nazis were confident that overdosing with Zyklon B would make up for any inefficiencies.

This is perhaps the most glaring example of you contradicting yourself, as you claim elsewhere that Nazis used just 300 ppm HCN, a concentration that is said to be the minimum fatal dose. This is not, however, a hallucination, but rather an accurate AI reproduction of the contradictory arguments Holocaust believers use.

Additionally, installing fans to circulate cyanide gas during operation would be dangerous for the SS staff, requiring far more complex sealing and filtration systems.

What can even be said in response to such nonsense?

You are deferring to somebody else's chemical arguments which have already been disproven in court by expert chemists. If you want to say that I am not qualified to figure out the technical details, then you aren't either and we have to defer to the actual experts who have already testified that Rudolf was wrong.

Rudolf's chemical arguments have not been disputed in court. They were rejected by a judge and he was criminally charged for offering them.

Zero experts have testified that Rudolf was wrong.

3. Alkaline conditions - Prussian blue forms best in basic conditions; gas chamber walls were often neutral or acidic, which inhibits the reaction.

The gas chamber walls would exhibit the same alkalinity as the walls of the disinfestation buildings, unless you have some contrary evidence.

4. Iron availability - Not all building materials (e.g. plaster) contain reactive iron compounds.

Okay, but the plaster's iron content has been measured. You're just wrong, as thoroughly explained in HansHill's post. Multiply this by however many times you repeated this falsehood.

The delousing chambers had exposed red clay brick walls which often contain hematite (Fe2O3) which can release iron ions that become chemically reactive over time.

Exposed red brick, you mean on the outside? The brick isn't exposed on the inside, where the gas was. The cyanide penetrated through the plaster to reach the brick.

In contrast, the extermination chambers were built with concrete or cement based plaster which have iron bound in silicates, but they are not chemically reactive. Because the extermination chambers lacked reactive iron, they did not have the necessary conditions to produce Prussian Blue.

Since I am not a chemist I cannot respond to this more definitively, but Grok AI lists hematite as the top iron compound found in concrete and cement. Iron silicate is one of the most rare or trace iron compounds, so it's really irrelevant to the discussion.

Crematoria II & III were reinforced concrete with interior plaster or lime wash coating. They were underground morgues (Leichenkeller 1) that were converted into gas chambers. The walls were coated in lime plaster, which is alkaline but lacks ferrous iron. The plaster coating limited exposure of reactive iron compounds, and the walls were smoothed and sealed—poor for cyanide absorption or reaction.

This is wrong because the walls are in fact coated with a plaster that contains iron, as you already admitted to on page 1. In BW5a it was the plaster that was stained blue!

---

I will stop there. By my count you have posted at least 11 AI hallucinations, that is, factual errors, in this thread. This is in line with what you, ConfusedJew, have done in previous threads. For example see here:
https://codohforum.com/viewtopic.php?p=10690#p10690

You absolutely cannot argue this way. Because you continue to do it, it's the functional equivalent of lying*. Now these lies are filling up the forum, which will in turn fuel future AI errors and confuse future researchers.

* If it is against the rules for me to say this, so be it. It is true.

[Nessie]

How do you know, that the walls of the gas chambers, inside Kremas II to V and the two farm house bunkers, never looked similar to that? The Prussian blue staining was probably not as defined or obvious as that, due to lower levels of exposure, but since those buildings were demolished, you do not know what the walls actually look like.

[HansHill]

When we review the material, both concrete and lime mortar are more porous than brick, not less. Which is the opposite to what you are arguing.

Likewise the diffusion properties of various building materials are known, and both lime plaster and concrete have higher diffusion co-efficients than brick when compared:



All of this builds us a compelling picture that the environment of the homicidial gas chambers is even more hospitable to PB formation than the delousing chambers on every metric you can possibly conjure.

I didn't mention porosity or diffusion. My research suggests that the homicidal chambers did not have enough reactive iron to form Prussian Blue.

Yes you did, you specifically argued that the building materials present were an inhibitor to HCN "absorption or reaction"

The walls were coated in lime plaster, which is alkaline but lacks ferrous iron. The plaster coating limited exposure of reactive iron compounds, and the walls were smoothed and sealed—poor for cyanide absorption or reaction.

I have countered that the properties of the building material support the effective absorption of HCN by giving you the porosity and diffusion properties of the materials. This supports that the HcN molecules will interface with the walls, and diffuse relatively unimpeded into the interior of the materials. This interfacing is supported by everything I have demonstrated to you, referenced and cited to the best rigorous standards available.

Rudolf's Work "The Chemistry of Auschwitz" has a dedicated section where he discusses all these properties and more - the relevant section is 6.7

See below section 6.7.2.2 where he expands on the absorption qualities of cement, all of which are referenced back to either rigourous building standards - The German Industrial Standard DIN 4108, part 4, or where relevant other primary studies that will be referenced throughout.

How do you argue that those properties make the environment "more hospitable to PB formation than the delousing chambers on every metric you can possibly conjure"? This doesn't make sense to me personally and I don't think that it makes logical sense at all.

Based on the characteristics we explored in the above - the building materials, their properties, the behaviour we can expect to find when HcN interfaces with the walls, all cited and referenced back to rigourous studies and building regulations.

In theory, concrete and lime could absorb more HCN than brick surfaces but more porous does not mean that there will be Prussian Blue. Porosity, absorption, and diffusion aren’t the limiting factor for Prussian Blue formation. The chemical reaction pathway is.

There's no "in theory" about it, this has been demonstrated - we understand the properties of these materials very well. The behaviour we are discussing is predictable, replicable and common.

For you to argue these properties are unfounded in some key way, or the behaviour would be something other than what we observe, you would need to give me something - anything - to substantiate your position. I think you, and everyone reading this, will appreciate that everything I have stated or offered is backed up rigourously - you (or your AI) haven't actually rebutted any of these points. I've not seen anything substantial at all, in fact quite the opposite; it seems your AI hallucinates on basic points such as the swivel door poisoning everybody nextdoor is acceptable, or building materials are acidic then immediatley correcting itself to alkaline, in your subsequent post.

All of this is explained very neatly - your AI is hitting guardrails from this material, and you are uncritically reproducing it. For example, just in this post above you say

I didn't mention porosity or diffusion.

You did, you just called in absorption. Again, like I said earlier, you seem like a High IQ operator and I trust you know these are related concepts. You are simply not critically analysing what you are producing.

As for:

My research suggests that the homicidal chambers did not have enough reactive iron to form Prussian Blue.

Again this has been measured. By Mr Rudolf, no less. We know the iron content present in the materials. Which falls exactly inline with the expert literature. As I said before, it's very telling that only Rudolf obtained iron content readings and Markiewicz for example did not. This indicates Markiewicz does not share this hyptothesis of yours - because it is ultimately, baseless.

[HansHill]

I will stop there. By my count you have posted at least 11 AI hallucinations, that is, factual errors, in this thread. This is in line with what you, ConfusedJew, have done in previous threads. For example see here:
https://codohforum.com/viewtopic.php?p=10690#p10690

You absolutely cannot argue this way. Because you continue to do it, it's the functional equivalent of lying*. Now these lies are filling up the forum, which will in turn fuel future AI errors and confuse future researchers.

* If it is against the rules for me to say this, so be it. It is true.

Excellent post - I think Wetzelrad has his on something important here. Many absurd, contradictory, or outright false claims have been uncritically reproduced here, all under the topic of "forensic chemistry at Auschwitz".

To be fair, Confused Jew is not the only one. From this thread alone, Nessie has stated that Krema II is not able to be examined (!) and Bombsaway has offered his theory of the bleached walls. These all represent data points which will fuel further hallucinations. I shudder to think my AI generations in other areas of life contain any "Nessie-isms". God.

For this i have a mod suggestion - if we (revisionists) were to flag a post which makes an absurd claim (such as the Kremas are no longer able to be examined) - the author is given one chance to offer a citation, and if this is not produced, the post is moved to a quarantine, or removed entirely.

This will not only help keep threads lean, but will over time incentivise these people to start hedging their words like "its possible that X is the case".