[Hermes]

In the previous post I discussed briefly the value of plotting Si/Al ratio in order to predict -with some reserve- the appearance of glazes. This time I like to show an example of a ternary or tri-axial plot based on the molar % of the glaze formula (in the analysis %).

The reading of this kind of plot requires a bit of reflection but once figured out, it again adds interesting information on the glaze(s).

The capability to predict the glaze appearance is somewhat less accurate than with the Al/Si plots, especially when Bore is used in the formulation. On the other hand I find that from scientific/technical viewpoint it helps to understand glaze chemistry.

What you need is molar % of the used elements. If you have a recipe, you can calculate this by hand but, this is rather tedious. A glaze software like INSIGHT can give it in 1 or 2 clicks. Then the different Mol% of the metals are grouped in Fluxes, Amphoterics and Glass formers. When % are calculated for each group, these values can be entered in the ternary plot template.

The template to make ternary plots is rather complex. I can provide it on request.

An example is at the end of the text.

In the example, WWW172 is likely to be a matt glaze, WWW390 has to rated as satin-matt and the other 2 glazes are probably glossy.

Next time I will discuss the relative importance of limit values for the common elements used in glazes.

We are still quite far away of 'putting things together ', be patient! In a few more posts to come, it will be revealed.

For information on glaze chemistry, visit my website at:

http://users.telenet...ics%20menu.html

[docweathers]

I'm looking forward to your next post on glaze chemistry.

[yedrow]

Thanks again. I'm curious, will information on the "grid method" in Ian Currie's book help to read this graph?

Edit...I think I get it.

Joel.

[Hermes]

yedrow, on 12 January 2013 - 06:34 AM, said:

Thanks again. I'm curious, will information on the "grid method" in Ian Currie's book help to read this graph?

Edit...I think I get it.

Joel.

I assume you have found out how it works. Just follow the tick marks for each group. The unusual thing is that they are inclined to an angle, that's all.

Thanks for your interest

[Hermes]

docweathers, on 12 January 2013 - 05:58 AM, said:

I'm looking forward to your next post on glaze chemistry.

Thanks for your interest, for the reviews and surely to have encouraged me to post.

[Marcia Selsor]

Great stuff!!! Many people on this forum could really use a good grasp of glaze chemistry. Your charts and explanations are simple to follow and very direct.
Thanks for posting.I think this should go under Glaze Technical rather than "In the studio" sub topic. I will ask the moderators.
Again, great educational resource!!


Marcia

[yedrow]

This is pretty exciting. I'm developing a couple of glazes and I'm interested in how well they match the predictions of this graph. Thanks again!!!

Joel.