Properties of Ceramic oxides: Opacifiers and Colorants (Free Online Glaze Course Part 6)

This is the 6th video in the Free online Glaze Course. I describe the properties of opacifiers and colorants. (Forgot to mention that you can get lavender/pinks with cobalt and magnesium oxide in the base.)

[@____Ann____]

Excellent! I am already looking forward to the next session. Thanks!

[@kevinh5024]

The Videos in this series are amazing. They are very educational. Thank you for posting.

[@chardee1694]

John.. I'm just new to pottery, your book was the 1st book I lusted for and bought, Im learning so much from your videos and am so thankful that you kindly share your knowledge. Thanks for all you do for the ceramic world... now I'm off to continue binge watching your videos 👍

[@virginiaperez7102]

So generous Thank you

[@Neldidellavittoria]

Apart from all the blues you can get with Co, an interesting colour is pink in the presence of Mg. Happened to me once by chance. I did some brushwork with Co on a that had quite some dolomite, and all the outlines of the brushwork turned bubble-gum pink. As always, thank you very much indeed.

[@johnbrittpottery]

Yes and lavender with magnesium also.

[@melaniewulforst6733]

Thank you for these videos!! So happy I found them!! I love your book and have revisited it frequently since graduating. I was curious - what do you think about colorant and water oxide washes applied to the exteriors of bisque, then wiped, and covered with glaze in regards to food safety? I have had such a hard time finding an answer to this. It seems many people don’t talk about it.

[@____Ann____]

I am wondering this too.

[@johnbrittpottery]

Hard to say. Depends on the amount. And various oxides move differently through glazes, like copper tries to move to the top and that is why it make black in larger amounts. Probably ok but hard to say unless you know specifics. Just send it in to be tested. I use Brandywine labs in Mass. Will ease your mind. No one can say for sure but testing will tell.

[@tejanored11]

Do you have instructions on reclaiming settled glaze . Thank you for your service. Just found your Chanel today . Excellent

[@johnbrittpottery]

2 videos on the channel...deflocculated glazes...

[@WhoaNelie]

Love your book and so happy to find your videos! thank you!! I use your book to make my glazes. the chemicals below the solid line on the ingredient list means what? They are very small amounts - do you liquify them first and add? thank you!!

[@johnbrittpottery]

Below the line are colorants, opacifier and suspenders. Just add as usual.

[@Caxap-u3q]

Hi John. Thank you for wonderful series! If I may suggest I tiny correction about nickel - it is NiO or Ni2O3.

[@johnbrittpottery]

Yes, Black Nickel is Ni2O3 and Green Nickel is NiO but this is a general overview. I also didn't include various valences of Co, Cu, Mn, etc. But thank you for writing!

[@kantamana1]

Very Helpfull, i took many notes! What about Cadmium?

[@johnbrittpottery]

I don't use cadmium or selenium, or uranium, etc.

[@momenatef3218]

Can i really do gold lusters by my self??? How?

[@EpiCai]

Thank you so much for sharing your knowledge John :) Is it possible to make my own Rutile from mixing Titanium Dioxide and Iron Oxide? What percentage of iron oxide should I mix to the Titanium Dioxide?

[@johnbrittpottery]

Hard to say as rutile is variable...try 3.5 titanium and 1 red iron....also go on the Facebook Group...Exploring Midrange Glazes Together with John Britts book...someone on the will know...great group. Also, John Britt High Fire Glaze Hroup, Ceramic Recipes.

[@EpiCai]

@@johnbrittpottery thank you John, will do :)

[@____Ann____]

Hi John. I know you are busy teaching. I love this series so much. Would there come a part 7? I am very curious about 'material families' . If I don't have f.e. Gerstley borate, what other materials are similar to be able to calculate a substitution. Continue the great work. You always explain so well.

[@johnbrittpottery]

Had 3 workshops cancelled so ...I will have time for the next video...give me a week or so.

[@____Ann____]

@@johnbrittpottery What a mess with this virus. Here all schools are closed for a month. I understand it is necessary but still. Looking forward to a new video!

[@abuzarmalik5353]

Hey I am from India. I basically own a Gas tunnel Furnace which is oxidation I think. And i can not get gerstley borate easily and other stuff. Can you please help with some materials substitute. And email address if you can give.

[@____Ann____]

Hope you are well. Your videos are being missed :-)

[@johnbrittpottery]

Been busy with a job...I will try to come up with one soon.

[@tejanored11]

John can I reclaim glaze that has settled over eight years

[@johnbrittpottery]

Yes

[@rondacorkhill1654]

Thank you for being non partisan. I've recently been inundated by individuals from a specific political party and this isn't where I expected that to happen.

[@johnbrittpottery]

I am not non-partisian but keep it to myself...no one wants to hear it.

[@rondacorkhill1654]

@@johnbrittpottery Even better.