impurities in metol?

[landstrykere]

just out of curiosity I wonder what this could be.
Three years ago I found a seller on Ebay and bought some metol because the cheap price. I still have some, it was in the back of a shelf.
I did mix many liters of D23 and other formulas from this batch, had no issues, but it seems to me it has some impurity,
If I recall well purity for photographic use must be >= 98%. So I wonder what are the opinions of the chemists here.

on this photo, a small box of metol as it is generally: a white powder. And the black plastic pouch with the other and it is grey. CAS and formula on the label matches metol.

https://i.postimg.cc/xQgZjTmx/IMG-1709.jpg

[Michael R]

Definitely not normal technical/photo grade. White/off-white is what it should look like.

Personally I would not use it but that doesn’t mean it won’t develop film.

[xkaes]

I agree. I would throw out the gray stuff, and that white powder looks more like borax.

[Mal Paso]

Who needs a lab when you can analyze a chemical just by looking?

Do a side by side comparison with a Metol only developer like D23.

[landstrykere]

Definitely not normal technical/photo grade. White/off-white is what it should look like.

Personally I would not use it but that doesn’t mean it won’t develop film.

I have use it with many sheets and rolls. Didn't notice anything. So didn't bother to compare (take two identical photos, develop one with D23 from usual metol, the other with the grey stuff). May have to, just mix 500ml of each for instance.

My idea was that impurity are inside the tolerance of photo grade use, but then no idea where to check for purity grade. 2% impurity could cause the different colour I guess but I am not chemist.

The listing is still there btw. When I buy chemicals I just check the CAS and formula, but then not all sellers display purity grade.
This seller description mentions photographic use, that's why I bought:

https://i.postimg.cc/08kwYH19/metol-prishib-1.jpg

https://i.postimg.cc/5fMv02PY/metol-prishib-2.jpg



btw I just saw another listing, with a photo of the grey stuff:

https://i.postimg.cc/CwH8fptv/metol-kharkov-1.jpg

https://i.postimg.cc/JMXZMkQC/metol-kharkov-2.jpg

[landstrykere]

that white powder looks more like borax.

the photo isn't a close up. The white powder is metol.

[Conrad . Marvin]

If you want consistency, buy good quality chemicals from a known manufacturer and source. Otherwise, test and correct for any discrepancies you find. If you don’t have any issues, then go for it.

[Mal Paso]

the photo isn't a close up. The white powder is metol.

Of course it is.

You can't judge the quality by looking. If the color disappears when you add sodium sulfite to the solution it may be oxidation.

Do a side by side test if it worries you.

I use Photographer's Formulary either direct or B&H.

[paulbarden]

All I am going to say is that I would never buy my chemistry from a business that sold brown or grey Metol. No thank you.

[landstrykere]

the photo isn't a close up. The white powder is metol.

Of course it is.

You can't judge the quality by looking. If the color disappears when you add sodium sulfite to the solution it may be oxidation.

I was simply mentioning to @xbaes that the white/whitish one on the picture IS actually metol. These powders are mine, I do use them, they are on my shelves. Not products I am considering to buy. As for reaction when mixing D23, the grey one produces a tainted solution, the white one not, solution is clear, slowly yellowing by oxydation with time as it should.


I use Photographer's Formulary either direct or B&H.

this is USA, me it's Norway, out of the question to buy stuff in USA. I could create a thread about options for buying in Europe. Unsure what are the proportions of members here by continent, btw.

[Michael R]

this is USA, me it's Norway, out of the question to buy stuff in USA. I could create a thread about options for buying in Europe. Unsure what are the proportions of members here by continent, btw.

Bellini (Italy) sells good quality raw chemicals. I’m not sure if they have a distributor/retailer in Norway but they are sold through several retailers nearby in Denmark, UK, Belgium, Germany etc. You can also try contacting them directly.

https://www.bellinifoto.it/en/where-to-buy/

Another good option in the EU is Fototechnik Suvatlar in Germany:

https://www.moersch-photochemie.de/wp-content/uploads/2023/04/Preisliste-online-2023.pdf

[landstrykere]

All I am going to say is that I would never buy my chemistry from a business that sold brown or grey Metol. No thank you.

when I bought the grey one I didn't know it was grey. Just found the ad on Ebay with the description, formula and CAS corrects and it does mention it is for photographic use.
I am used to the fact that here in Europe when you buy something, conformity to description is correct.

That one seller btw is on Ebay since 2013 with a long positive record, they sell all kind of chemicals, some used in photography. Sometimes a purity level is mentioned, for instance the phenidone B they sell, as 99.9%:
https://www.ebay.com/itm/204538525619?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=Id2NTy8eR4a&sssrc=2047675&ssuid=Gn5OrD6MT4-&widget_ver=artemis&media=COPY

[landstrykere]

Bellini (Italy) sells good quality raw chemicals. I’m not sure if they have a distributor/retailer in Norway but they are sold through several retailers nearby in Denmark, UK, Belgium, Germany etc. You can also try contacting them directly.

https://www.bellinifoto.it/en/where-to-buy/

Another good option in the EU is Fototechnik Suvatlar in Germany:

https://www.moersch-photochemie.de/wp-content/uploads/2023/04/Preisliste-online-2023.pdf

thank you, I am familiar with options in Europe in general, or EU in particular :-) ...Mainly:
- Suvatlar in Hamburg
- Bellini in Italy
- Disactis in France
- Laboratorium Discounter in Netherlands
- Manis in Greece
- Warchem in Poland
- Ximmag in Russia

not all have everything, Suvatlar and Ximmag has the most.

My favorite one is Ximmag because it's a brick and mortar shop in downtown Sankt-Peterburg, by Kokushkin bridge on Griboedova canal.
Imagine this: you stroll in downtown Sankt Peterburg, come nearby, push the door, order metol, pyrocatechol, sulfite, whatever at the counter, a guy goes in the back to prepare the order and hands it to you. Like you buy your beer or your groceries.

this shop:

https://i.postimg.cc/Chj7f4PV/himmag-1-800.jpg

https://i.postimg.cc/CFnmw0b5/himmag-2-800.jpg

for instance there I bought metol, hydroquinone, pyrocatechin, natrium sulfite:

https://i.postimg.cc/Vfy46hFR/himmag-3-800.jpg

1 kg metol, 14500RUB ~ 145EUR:
https://himmag-spb.ru/metol/ but they don't ship abroad.

Next good source for metol is Manis in Greece: 1kg 135EUR and they ship abroad:

https://manischemicals.com/el/-a-yles-photografikon/1729-metol.html


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Norway is NOT in EU, it means :

- shipment is often quite more expensive, because EU countries use a common pricing grid. For instance my place near Oslo is much closer from Hamburg than Rovaniemi in Finland, but shipment from Hamburg to Oslo is much more expensive than to Rovaniemi, because i am not inside EU zone.

- customs: 25% + processing fee and sometimes cumbersome communication with customs when they receive and inspect the parcel and want to know what these powders are.

In fact I use an address in Sweden, because I am lucky border is 70 kms from my place. So I order and get shipped to Sweden, because it is in EU. I spare VAT, processing fees and customs agents wanting to know if I do bombs or narcotics.

Suvatlar himself prefers to send me chemicals to Sweden, too, because on his side it is also a hassle to do the customs declaration.

[Gabe]

You can't necessarily tell much from a discolouration. Often it doesn't take much of an impurity to do that. Metol is not at all difficult to synthesise, so in all likelihood the material is OK, but the only way to know accurately is via analytical techniques using instruments no regular person has access to (LCMS, NMR etc).

[landstrykere]

You can't necessarily tell much from a discolouration. Often it doesn't take much of an impurity to do that. Metol is not at all difficult to synthesise, so in all likelihood the material is OK, but the only way to know accurately is via analytical techniques using instruments no regular person has access to (LCMS, NMR etc).

btw I asked the seller, his answer I guess he mispelled metol:
"The metal darkens over time but does not lose its properties. Perhaps you were sent the previous batch. The metal is white only a few months after production. Usually there is coloring."

[Gabe]

btw I asked the seller, his answer I guess he mispelled metol:
"The metal darkens over time but does not lose its properties. Perhaps you were sent the previous batch. The metal is white only a few months after production. Usually there is coloring."

Yes that can happen too over time. The typo doesn't exactly inspire confidence, but perhaps a product of auto-correction.

[Mal Paso]

Spell check like government always watching over your shoulder, seldom has the correct answer. Metol becomes metal with the limited standard dictionary. Happened to me just now.

Metol always looks a little weird. A little dirty, like an occluded crystal.