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Comment by Maulik Oza on January 20, 2014 at 9:42pm

ok... now i got both the things clear in my mind..we were trying to achieve this kind of luster in raku. because i didn't know about this technique.. i knew little bit about luster fuming but this is fascinating. i will try to search about this more in our locality and do some experiments with it. i will keep you posted.. and this golden tea pot is superb...:)

and ya if you can share that mixture which you have developed i will try that also....is it the similar mixture to saggars in factories because they also mold or press cast many solid things like burner blocks and all..

Comment by Norm Stuart on January 20, 2014 at 9:00am

Metal vapor deposition or sputtering was developed in making electronics and aerospace parts.

You place things like ceramic to be plated inside a vacuum chamber. A vacuum does not conduct heat, nor does it stand in the way of the spray of molten metal plasma.

Then metal is heated on an electric burner until it vaporizes into a plasma. Every thing else in the vacuum chamber will be cool, so the metal vapor condenses on the ware and the inside of the chamber.  This is how the reflective layer is added onto mirrored sunglasses. Depending on the metallic material heated, magnets can be used to help direct the metal plasma onto the ware.

http://en.wikipedia.org/wiki/Physical_vapor_deposition

This is an article about PVD onto ceramic written by a Canadian artist who visits Jingdezhen China.  The metals they're using are far harder and more durable than gold or platinum.

http://www.alluvium.ca/Essays/CM_AllThatGlisters.pdf

There is also chemical vapor deposition process, but this is not as applicable to ceramics.

http://en.wikipedia.org/wiki/Chemical_vapor_deposition

I look forward to seeing architectural work over the coming years.  Seeing the actual buildings Alexandre Bigot clad with ceramics in Europe was amazing, only more so once you realize they're kiln-fired ceramics and what he had to overcome to make ceramic pieces essentially without clay.

The resulting mixes of puck shapes I've made hold glaze well and are very durable and don't break when they're dropped.  I have a gallery of some of Bigots work.

http://community.ceramicartsdaily.org/gallery/album/679-alexandre-b...

As for the metallics, is this 835.00 € "gold" ceramic teapot offered by KaDeWe in Berlin was applied with a sputtered plasma rather than traditional gilding, or a gold gilding over a harder sputtered metal like titanium?

https://www.artedona.com/en/Dinnerware/Dinnerware-with-gold/Sieger-...

Comment by Norm Stuart on January 20, 2014 at 8:49am

Kaolin platelets provide the plasticity for forming a clay body.  But this also creates constraints on thickness as kaolin gives-off 12% of its weight as super-heated steam around 565C as it decomposes into meta-kaolin.  Being a chemist Bigot realized he could make thicker pieces by not using kaolin - using only material which does not give off gas when it's fired in the kiln. 

The challenge is to find a mix of materials which can be melted together with enough fibrous texture to provide strength to hold the piece together before it's fired. This is his 1906 Patent in the US which describes the concept but not the material.  He created a mold which he painted with glaze, shoveled the dry clay-replacment into the mold and used a hydraulic press to compress it. He called his mixture Grès Flammé.

http://www.google.com/patents/US838496

My guess was to start with Wollastonite (Calcium Silicate) which is naturally fibrous and compressible, then add Kyanite (previously fired clay which develops a needle structure - used as a raw material for lab crucibles used over open flames as the needles interlock when fired in the kiln).  The I need something which melts at a lower temperature like Boron, Talc (Magnesium Silicate), Lithium, Potassium Feldspars or man-made frits (glass with lots of fluxes like boron, lithium, potassium, calcium, sodium etc.

But all of this has to be material with very low LOI (Loss on Ignition aka firing).

http://digitalfire.com/4sight/material/wollastonite_1705.html

http://digitalfire.com/4sight/material/kyanite_951.html

http://digitalfire.com/4sight/material/talc_1620.html

http://digitalfire.com/4sight/material/nepheline_syenite_1069.html

http://digitalfire.com/4sight/material/custer_feldspar_253.html

http://digitalfire.com/4sight/material/ferro_frit_3195_356.html

Looking at these materials, only the Talc needed to be prefired at ^014 to drive off the water.  I've sieved together different mixtures of these materials.  They can all be formed under pressure and fired as thick as you prefer. Some hold more detail than others and some are more or less porous.  But a lot of them look just like Bigot's fired pieces I saw and touched at the Applied Arts Museum in Budapest.  Like this 8 foot tall parapet.

or this balconey

or friezes

The photos are all in my gallery, or look up his architectural ceramics in Google.

Comment by Maulik Oza on January 20, 2014 at 5:03am

Norm..Norm..Norm...
your answers are always above my expectations...and makesme happy to see them.:)
i didnt know about this village and also about alexander bigot..... you know my dream is to make studio which produces architectural ceramics and then i can use them in my buildings. this pictures will inspire me a lot..

two things i didnt understand are the metal vapor deposition in a vacuum and your last sentence about ceramic mixture... can you please explain that in detail.

Comment by Norm Stuart on January 20, 2014 at 1:16am

Maulik -- Are you aware of a Chinese village, Jingdezhen, which has been making porcelain for 2,000 years.

They have access to even more cool toys than you do - with very low wages.

This is a video of a Japanese ceramacist who has moved to Kingdezhen to have his works made there.

http://www.youtube.com/watch?v=9MSxEAekY1U#t=0

I just found they also do metal vapor deposition in a vacuum, in place of gilding.

I can't even imagine having our own tunnel kiln.

I've been pretty amazed with the architectural ceramics from the arts and crafts period made by Alexander Beegoo, actually Alexandre Bigot in French.  1862 to 1927.  He used previously fired ceramic material with a binder to free his works from clays constraints on size on thickness.

This is a photo of the front entrance of his home decorated with fired ceramics.

and the entire exterior, also primarily kiln fired ceramics.

The largest producer of architectural ceramics until he closed his studio in 1914 during WW-1.

I've tried some ceramic mixtures which don't off-gas around 565 C if you're interested.

Comment by Maulik Oza on January 19, 2014 at 11:35pm

and yes another thing norm... i am planning to make roller kiln 25feet long for our studio.. once i will start working on it i will post some pictures.. if you have any information regarding this and if you can share it will be great..:)

Comment by Maulik Oza on January 19, 2014 at 11:26pm

hi, norm

thank you for appreciating the work. and yes kiln is working fine.. i am not applying any coating right now..because i want to see how much it changes over period of time. let see ..

Comment by Norm Stuart on January 19, 2014 at 8:55pm

Wow.  You got the raku kiln up and running.

Are you coating the fired finish with a plastic spray to protect the metallic finish from oxidizing over time?

Some raku glazes seem more durable than others without protection.