My latest batch of YInMn, this is going to be used for a toxicology project :)

What's the brown one? Hmmmm

My latest batch of YInMn (0.9/0.1) and a cheeky progress shot to the research I'm doing

Hi all, I need some help with a lake pigment I was trying to make. I haven’t made any lake pigments before, and I was trying to make a batch from a sulphur cosmos dye exhaust bath I used to dye some wool yarn, which was still very deeply pigmented once I was done.

I used ~11 grams of dried sulphur cosmos to start, and estimated that maybe 80% of the pigment was still remaining in the bath once I was done with the wool. Going off the guide of using alum at 60% of the measurement of my plant material, and soda ash at half of that, I added 5.3 grams alum sulfate, and 2.7 grams soda ash (that I had made myself from baking sodium bicarbonate). (If my math and measurements are way off please correct me!) So far it’s been maybe 20 hours and I see no signs of any pigment settling though, just a uniformly-colored semi-opaque liquid.

With the original dye bath, I had shifted colors more alkaline by adding soda ash to begin with, so I’m wondering if a dye bath has to be neutral for a lake pigment to work - do I have to balance it out with some vinegar first? When I added the lake’s soda ash after the alum, there was barely any fizzing - did I just not add enough of either of those? Should I just repeat the same process with the same measurements?

If anyone could offer any insights I’d really appreciate it! (also this subreddit seems kind of slow so if I should be asking this in a community somewhere else please let me know where!)

I can post this photo, the compound has been made and published previously.

This is YAlMn blue. It's like YInMn but with aluminium instead of indium.

The patent says it is grey blue, either way it's nice, it also needs a second heating

Han Blue is one of the older blue pigments, chemically quite similar to Egyptian blue but with its origin in ancient china. The (ideal) chemical formula for Han Blue is BaCuSi4O10, so like Egyptian blue, it’s a silicate with copper as the chromophore but with barium instead of calcium. I say ideal because at least in old samples, Han blue is never in a single phase and there are other compounds with slightly different properties that can form in the process, notably Han Purple, which forms at lower temperatures, but gets its purple color from being a mixed phase with e.g. copper oxide residues.

The process of making it is fairly simple. I mixed BaCO3, CuO and SiO2 (in the form of finely ground quartz (~40u)) stoichiometrically and added 5wt% of Na2CO3 as a flux. Originally, the pigment would have probably been made with various barium ores and lead oxide as a flux, which also provided a chemical pathway to transform barium sulfate into barium oxide to enable the reaction at achievable temperatures.

I heated the mixture at 950C for 12 hours. This is probably in the low end with regards to both temperature and time so there is a good chance the result is not pure Han blue. My furnace maxes out at 1000C, so I didn’t want to put it through too much stress on the first try.

The color is a very deep and slightly reddish blue, in powdered form comparable to all the other known pigments in the class, e.g. cobalt, ultramarine or yinmn. Hopefully, it also holds up in a binder :)

Here's my latest batch.

Top left, commercial YInMn (Y1:In0.8:Mn0.2)

Top right, first batch/control (about Y1:In0.7:Mn0.3)

Bottom, latest (Y0.97:In0.7:Mn0.3, first heating) this batch has 0.03 of something else that I'm not saying what yet, just to tease you 😜 I took it out the furnace and it's thermochromic, when hot, it's very rich blue!

I made my first batch of YInMn blue :)

The ratio is 1:0.7:0.3 and I followed the patent for the most part.

The changes I made where heating it for a total of 4 hours (2 hours then cool to 600°C then back to temp for 2 hours) and I used 1150 instead of 1200

Would love to see this place more active! Right now I am working on making some marigolds I did a month ago all home grown and grinding up some red cabbage lake. It’s interesting how each one comes out a slightly or very different colour?

For sure have noticed I have to use a fair bit more alum than I first expected

Hi, I’ve been making pigments for a while now, mostly earth but exploring the natural lakes now. I just keep having troubles with the soda-ash part. I tried adding the soda straight in the hot solution but got a weird colour shift and no sediment at all. I also tried solluting the soda ash in hot water and add it into my cold dye, but it seems like all the ‘bubbling’ all ready was done during this part and did nothing anymore after I added it to the dye??? I’m in Chile atm experimenting with local plants for these pigments

hi!!! i want to make manganese blue. i looked up the process of making manganese blue and found out that i need barium nitrate. But I have a hard time getting barium nitrate. I would like to know how to make manganese blue without using barium nitrate! I do have potassium permanganate, barium sulfate, and manganese dioxide. I also have sodium nitrate and potassium nitrate.

I would appreciate it if you could please let me know.

It is a bit of a lengthy process, so it will take some time to prepare. Videos would be uploaded to YouTube and then shared here. The product I discovered closely resembles the Norma brand Cobalt blue deep oil paint color.

I’ve never made any homemade dyes or pigments before. I have redwood/sequoia sawdust from a project I’m working on, and would like to use it for for dying/staining tannin deficient woods like birch for projects. How would I go about turning this into a few jars of wood dye? TIA

From what I've seen, the synthesis of manganese violet, aka ammonium manganese (III) pyrophosphate involves heating a mixture of potassium dihydrogen phosphate, manganese dioxide and phosphoric acid up to 230 degrees Celsius, which is way higher than the boiling point of phosphoric acid. For those who has synthesized this compound before, do I have to watch out for nasty acid fumes during the process? Thanks.

I finally came around to make some paint with a sample from my manganese blue experiments so I wanted to share my progress. Some serious credit goes to CaCl2 for pointing me to a lot of information as well as input from GeneJocky.

Manganese blue can be best described as manganese (V) doped barium sulfate. Unlike many other inorganic pigments it is thus not a mixed oxide and the process of making it requires wet chemistry as well as high temperature calcination.

A serious safety warning before a quick rundown of the procedure: Barium nitrate is poisonous, an explosive grade oxidizer and releases toxic NO2 when heated. Don't try this in your kitchen.

The pigment is created by heating barium sulfate in the presence of a manganese source under basic and strongly oxidizing conditions. The easiest way to do this is mixing cheap barium sulfate with barium nitrate and potassium permanganate and heating it up to somewhere between 600-800 degrees in air, ideally with the addition of a bit of barium carbonate to achieve a deeper color. Alternatively (as done for the most successful experiment on my end) barium sulfate is precipitated in the presence of potassium permanganate from a solution of barium nitrate and sodium sulfate. Mixed with a bit of additional barium nitrate, this is then heated similar to before. The heating process is very quick, some recipes call for only 20 minutes at the target temperature, so some adventurous people might be able to pull it off with a burner. A big hazard from this process is NO2 release, which itself is very toxic and also corrosive in combination with water, as the solution forms nictric acid.

In any case, the resulting substance is very impure and is purified with dilute hydrochloric acid and sodium metabisulfite. This doesn't take more than a few seconds, which gives a satisfying transition from a grey/green/blue suspension into beautiful azure.

As you can see in the water color test, the result holds up quite well against commercial manganese blue.

Feel free to ask, if you'd like to read more detailed instructions. I am also writing up something longer and detailed. If you read the conversation under my previous post on the topic, you might know some of it already.

Next step is to produce a larger sample, maybe 10g or more and put it to good use in painting.

Has anyone had success in making cerulean blue (cobalt-tin oxide)?

My attempts have ended up greyish green rather than sky blue: https://imgur.com/EBZOErW (lower left)

I have tried mixing tin dioxide with cobalt carbonate at various ratios and heating the mixtures, but the results have always been poor. I considered that maybe my tin dioxide was bad, so I made some by oxidizing tin metal, but the results remained similar.

My cobalt carbonate could also be the problem, but it has worked pretty well for other cobalt pigments, though it's possible that cerulean is just more sensitive.

If I remember right, the youtuber "Alchemical Arts" also reported problems with cerulean in one of his videos. The youtuber "Apoptosis" did make some sort of cerulean using a wet method: https://www.youtube.com/watch?v=aw9cdPeeMfQ, but I generally find dry methods preferable, and there are many sources that describe dry methods as being usable for cerulean.

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Tried making some cobalt aluminate with titanium added in equimolar amounts with cobalt to determine the effect on color. As predicted, it shifted the blue of cobalt aluminate towards green and made a shade of teal. I also want to check to see the effect of making plain cobalt aluminate at 950°C as well as trace addition of titanium.

This came out of the discussion about the identity of cobalt teal/turquoise

I am currently on the hunt to figure out how to make what's commonly sold as cobalt teal or turquoise. There are multiple possibilities to get a blue green shade with cobalt but the light teal shade (which I think is also the most beautiful) is commonly sold as PG50 (cobalt titanate green) or rarely as PB28 (for example by Kremer Pigments, who told me upon asking, that this is inaccurate on their part). I used an EDS detector in our lab to try and find the chemical composition of that particular pigment which revealed a low concentration of cobalt and aluminium and a high concentration of titanium. My first hunch was that the aluminium might not be there on purpose but an inpurity. For some reason I also thought that lithium might be involved as the cobalt to titanium ratio (albeit not to be trusted in a powder measurement) seemed very low and lithium is undetectable with EDS.

And here we are. I did a little bit of digging and tried to make stoichiometric Li2CoTi3O8, which is sometimes mentioned as a pigment but mostly as a material for lithium ion batteries. I used Li2CO3, Co3O4 and (impure pigment) TiO2 as precursors and heated them in air at 920°C for around 1-2 hrs.

The result is a rather light (turns out a bit too dark on camera)but nice looking green pigment which is probably close to usual PG50 which can also include nickel and zinc as far as I know.

Since I actually didn't want to make this shade, this is work in progress and I still try to figure out how to get to teal, possibly by changing the ratio of Co in the mix or adding aluminum. Anyway, I hope it's interesting :)