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Post by jfox on Mar 12, 2017 10:11:56 GMT -6
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gczop
Full Member
Posts: 202
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Post by gczop on Mar 14, 2017 9:45:37 GMT -6
Jim,
The text Synthesis, Properties and Mineralogy of Important Inorganic Materials by Terence E. Warner chapter 17 Gold-Ruby glass...
has the full treatment. Photo shows clear glass 1400c and then red ruby annealed/struck at 650c. A remarkable reference: chap.9 PZT, chap 14 willemite etc.
G
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Post by jfox on Mar 14, 2017 10:46:34 GMT -6
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Post by Bernhard Schärf on Mar 18, 2017 4:15:57 GMT -6
Besides how amazing it looks under UV light it doesn't turn yellow - so it's not beta willemite - if I'm understanding correctly. Can the magnetic forces, Curie Temp theory be tested in some way? Arnie Hello Arni, yes, with the term Willemit is not always clearly evaded in the literature. It is sometimes referred to as Willemit, meaning aplha-Zn2SiO4. The yellow / green flourescence is not always clearly shown in the literature. I'm picking up a suggestion from Gordon, trying with / without Titan .....I once again looked at all of your attempts again and also recognized green structures. Perhaps the effects are also a mixture of different crystal structures. A further idea are titanates (Zn2TiO4 / ZnTiO3, Co2TiO4). Zn2TiO4 gives white colors and Co2TiO4 green. Mixtures (for example ZnCoTiO4) can also be formed. Zn2TiO4 (zinc orthotitanates) have a cubic inverse spinel structure and ZnTiO3 (zinc metatitanates) has a hexagonal ilmenite structure. The range for ZnTiO3 is 670 ° - 800 ° C. That might explain why the blue background at 1650 F comes back. A radiographic crystal phase determination, e.g. At a mineralogical institute could create certainty. Bernhard |
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Post by Arnie Benton on Mar 18, 2017 8:01:40 GMT -6
For the theorists, some more data to consider. Here's varying amounts of Ti - First a glaze with only Co as coloring oxide - Ti 1  Ti 5  Ti 10  Next, a glaze with Ni Cu Fe Co Mn Ti 1  Ti 5  Ti 10  With Co alone, Ti 1 seems no different than my usual Ti 5 pieces, but Ti 10 drastically changes the ground. With the multicolored glaze, Ti 1 looks so different it could be a mistake in the glaze mixture - and Ti 10 changes the ground - In my next firing I'm going back to the artistic side of the equation and testing other coloring oxides and variations. Arnie |
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gczop
Full Member
Posts: 202
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Post by gczop on Mar 19, 2017 8:50:50 GMT -6
Arnie,
Are these latest with a two layer glaze and/or the CaCO3, TiO2 combination used earlier?
Gordon
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Post by Bernhard Schärf on Mar 19, 2017 9:36:28 GMT -6
In my next firing I'm going back to the artistic side of the equation and testing other coloring oxides and variations. Arnie First of all thank you for the many attempts, I have learned a lot. A lot of success with further tests with the different color oxides. Bernhard |
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Post by Arnie Benton on Mar 19, 2017 14:16:20 GMT -6
Gordon - they're all 2 glazes, with the Ti, CaCO3 in the bottom glaze and the coloring oxides are either in the top glaze or both.
Bernhard - I thank YOU for your input and encouragement.
Arnie
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Post by Bernhard Schärf on Mar 20, 2017 3:35:25 GMT -6
Perhaps still a thought concerning the Zinktitanate ....... Small amount of WO3(Wolfram(VI)-oxid) <1 % accelerated the decomposition of hexagonal ZnTiO3 phase to cubic Zn2TiO4 phase. , while excessive addition ( for example 3% ) restrained the decomposition. WO3 affects the dielectric properties of ceramics …. Is worth a try ... Bernhard |
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