Deep Black Glaze

[okrish]

I am looking for the deepest blackest flattest glaze out there. I know there are many good black glazes, but I am specifically looking for something that is very flat and very black.

For reference, I am looking for something as close to the product "Black 4.0" as I can get. I know that something like that is probably not actually achievable, But I would like some suggestions for the closest thing in that direction.

The inspiration is for it to feel like you are looking into space.

This will be used on a cup so I would prefer it to be an actual glaze and not just paint it with black 4.0 or something.

The clay body will be white and that unfortunately can't change. I am wondering if I need to use a black underglaze first, but I am worried about brush strokes coming through.

 

Thanks!

[PeterH]

As in "Black 4.0 is the blackest paint you can buy"?
https://boingboing.net/2023/11/01/black-4-0-is-the-blackest-paint-you-can-buy.html

[okrish]

Peter, Yes! thanks for the image. I guess I should have added something like that for clarity.

[Mark C.]

At cone 10 sure but what is your firing temp ?cone 06 cone 6 something else ??

[okrish]

3 minutes ago, Mark C. said:

At cone 10 sure but what is your firing temp ?cone 06 cone 6 something else ??

Mark, good point.

I am currently firing at cone 6. I am reluctant to change that, but if switching to cone 10 can get me much closer to that pure-black look then I might be willing to make that transition in the near future.

[Min]

Would the black glaze be for both the liner and the outside of the cup? Recipe or commercial glaze?

[okrish]

10 minutes ago, Min said:

Would the black glaze be for both the liner and the outside of the cup? Recipe or commercial glaze?

Ideally for both inside and out. But if no food-safe options are available I might consider doing the inside differently than the outside.

Also, ideally, commercial glaze, but again if no other options I might consider a recipe.

But at this point, all options are on the table if the result is good enough.

I guess this brings up the question of what would I consider good enough. I have tried Amaco, Mayco, Georgies, and Cyote black glazes. The Mayco Satin black SW-140 is probably the closest to what I am trying to achieve. I have seen a glaze by Spectrum (253 Satin Black) which looks pretty good too but have not tried it yet.

I am curious if anyone has found a glaze or process (that they are willing to share) that really stood out in this regard.

[Mark C.]

since its only one cup I would go with a commercial glaze this will be the least painful process

My  Zacks black is a cone cone  9-11 and uses lots of colbalt Oxide   and is very simple (about 3.5%) Nepy syi and alberta slip

I have no idea at cone 6 as thats a temp I just move threw  fast to get where I'm going.

It varies at temp and location from gunmetal to shiny black

If the liner get on this glaze it will show blue line as its an oversaturated cobalt glaze

You are referencing paint colors and for me that ls a unclear thought process as glaze is glaze and paint is not

It was published in Ceramic Monthly a few years back as well-just google my articles in CM for the formula

[okrish]

22 minutes ago, Mark C. said:

since its only one cup I would go with a commercial glaze this will be the least painful process

My  Zacks black is a cone cone  9-11 and uses lots of colbalt Oxide   and is very simple (about 3.5%) Nepy syi and alberta slip

I have no idea at cone 6 as thats a temp I just move threw  fast to get where I'm going.

It varies at temp and location from gunmetal to shiny black

If the liner get on this glaze it will show blue line as its an oversaturated cobalt glaze

You are referencing paint colors and for me that ls a unclear thought process as glaze is glaze and paint is not

It was published in Ceramic Monthly a few years back as well-just google my articles in CM for the formula

The thought process is to provide the reader with a reference for making a suggestion. Flat, black, low reflectivity. I understand that glaze is not paint.

Thanks for the suggestion!

[Mark C.]

Zacks black can be gunmetal black at cool cone 9 temps in oxidation -if applied to thick it will crinkle up a bit as well-I suggest below approach .

Another approach is use a matt glaze base and add cobalt ox  or mason stain (the stain is the way to go I feel) to obtain the effect you are looking for. This will take a bit of testing you could start with mason 6600

Edited July 21 by Mark C.

[Min]

Thanks for supplying the extra information @okrish, makes it easier to offer help when we can narrow down some possible solutions.

Given you have already tried a number of commercial glazes I would suggest taking the one that gives you the closest finish (matte/flat) you are trying to achieve then if it isn't black enough you could add some Mason Best Black stain to it (#6600). Like Mark said though whatever clear liner glaze butts up against it will more than likely take on some of the pigments from the glaze stain to leave some colour to the liner. If you find the glaze is too matte you can add a small amount of a gloss glaze to ameliorate it. It would take some testing to dial in the least amount of stain needed.

I wouldn't use a black underglaze under an opaque black glaze, odds are it's not going to show through.

Matte glazes are not a great choice for liners, they tend to cutlery mark and sound unpleasant when cutlery is used on them. Also, a glaze loaded with pigments,like many black glazes are, can be prone to leaching. Don't know how much glaze testing you have done but a  couple simple tests to rule out a glaze for leaching and durability are here if you need it.

[okrish]

Mark, Min,

Thank you very much for the suggestions. Sounds like I will likely need to dive into mixing my own glaze for this one. I will try the Mason Best Black and go from there.

And good to note on Leaching!

Will report back if It turns into something cool.

Thank you!

[Bill Kielb]

2 hours ago, okrish said:

Sounds like I will likely need to dive into mixing my own glaze for this one.

Good choice on mixing, just to be aware with glazes you are not likely to achieve the surface characteristic of the black 4.0. It is still a glass, matte glazes are a bit rougher on the surface and definitely refractive, so the surface will likely never be near the super dry matte of the 4.0. You actually may get a desired effect of extreme black underneath a very clear glaze.

[PeterH]

8 hours ago, Bill Kielb said:

Good choice on mixing, just to be aware with glazes you are not likely to achieve the surface characteristic of the black 4.0. It is still a glass, matte glazes are a bit rougher on the surface and definitely refractive, so the surface will likely never be near the super dry matte of the 4.0. You actually may get a desired effect of extreme black underneath a very clear glaze.

Firstly, I don't doubt Bill's advice that a clear glaze over a black glaze may make it appear blacker.

However IMHO it emphasizes the real differences in the physics of Black 4.0 and glazes (pedantically the surface of the Black 4.0 pigment and the surface of glasses/glazes). Because covering Black 4.0 with a varnish seems to loose the magic †.

Black 4.0 claims to reflect about 0.05% of the incident light (this varies with the incidence angle of the light ‡). For window glass (and presumably glazes, which are glasses) the figure is a lot bigger (even with an anti-reactant coating).

 

† https://help.culturehustle.com/en-US/articles/black-40-faqs-121873
No, sadly this paint is not waterproof and may get damaged outdoors. There is no clear varnish as matte as this paint to protect it and attempting to use any top coat over BLACK 4.0 will likely ruin the finish.

‡ https://www.dpreview.com/forums/thread/4739693
Black 4.0 - deeper into the Dark Side?

PS If pressed I'd be inclined to try these options.

1) A clear base glaze containing lots of black stain. Maybe looking at the difference in appearance a matte base-glaze gives.

2) A deeply matte copper oxide surface (based on a copper matte raku but without the color-forming reduction). Wildly non-functional, but the optics might be interesting. I haven't tried it but Hasselle Copper Matte is  a frit/glass less copper matte recipe in
https://ceramicartsnetwork.org/docs/default-source/uploadedfiles/wp-content/uploads/2015/08/15rakuglazes.pdf

Edited July 21 by PeterH
Added Hasselle Copper Matte reference

[Bill Kielb]

4 hours ago, PeterH said:

However IMHO it emphasizes the real differences in the physics of Black 4.0 and glazes (pedantically the surface of the Black 4.0 pigment and the surface of glasses/glazes). Because covering Black 4.0 with a varnish seems to loose the magic †.

Black 4.0 claims to reflect about 0.05% of the incident light (this varies with the incidence angle of the light ‡). For window glass (and presumably glazes, which are glasses) the figure is a lot bigger (even with an anti-reactant coating

I think this bolsters the idea that a matte glaze very likely will not have the same effect as your black 4.0 especially the surface quality, so an alternate look may be acceptable. Test covering your laptop with matte and gloss clear might help with developing an acceptable look, similar to what you might expect covering an underglaze with clear glaze.

Edited July 21 by Bill Kielb

[PeterH]

1. Far more detail on carbon-nanotube based  black paints than any of us can handle.
https://www.paint.org/wp-content/uploads/2021/09/Carbon-Nanotube-based-Black-Coatings_Mar-2021.pdf
I think it clearly indicates that this class of material is in a different league from anything you will be able to achieve with a glassy glaze.

2. Although it won't be very robust, it might be fun to glaze a teacup with a black glaze and then  paint the outside with Black 4.0.
- there are several options for handling the outside of the cup
-- leave unglazed then paint with 4.0 (maybe over an acrylic undercoat)
-- paint the 4.0 on top of the glaze (maybe over an acrylic undercoat, perhaps one sold for acrylic-on-glass work)
-- maybe leave a lip-ring of untreated glaze (H&S, wear, etc)
- Looking at how stained my tea mug gets (and how difficult it is to clean) I don't think it's sensible to try and paint the inside of the cup.

3. In some ways Black 4.0 is reminding me of day-glow colours. Both are, I suggest, so dramatically eye-catching because the human visual system has difficulty assessing the reflectance of the surfaces (almost zero for 4.0 and "greater than 1" for day-glow colours). The day-glow phosphors convert UV light to a narrow visible band, so more light is emitted  by the object in that waveband than hits it.

[Kelly in AK]

In case someone reading the thread becomes so intrigued with Black 4.0 they simply must order it, I feel obliged to make a little public service announcement. I ordered some about two and a half months ago (May 7). It’s not here yet. I waited till the two month mark to email them and got an auto generated response apologizing for the wait and informing me that I was near the “top of the queue.” Poking around the web a bit I see this is a common experience. So, be prepared to wait, I guess. 

[neilestrick]

As black glazes become more matte they become more grey/metallic. A glossy black can be very black despite it being glossy, and will be blacker than a matte black. As others have noted, you're not going to find a glaze that has the non-reflective quality of the Black 4.0 simply because that's not how glazes work. It can only be so matte and still melt. A black underglaze can be quite black and non-reflective, but it's not going to be food safe because it doesn't go into melt like a glaze. If food safety was not an issue you could go that route, or possibly even use black stain in a porcelain clay body.