Babs Posted January 12, 2016 Report Share Posted January 12, 2016 Was reading last night that spodumene was used to make a toasty coloured clay body but required quite a percentage to do so. I wondered if anyone has done a wash on clay using Spodumene , in a similar manner to that of the soda wash? Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted January 12, 2016 Report Share Posted January 12, 2016 Why not make a high spodumene slip to dip pots into? Link to comment Share on other sites More sharing options...
Babs Posted January 12, 2016 Author Report Share Posted January 12, 2016 Yeh good point. I was wondering if anyone had gone down this path , but will do so High Bridge, a slip makes more sense than a wash. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted January 12, 2016 Report Share Posted January 12, 2016 Don't let that stop you trying a wash Link to comment Share on other sites More sharing options...
glazenerd Posted January 12, 2016 Report Share Posted January 12, 2016 Babs: Call it the Star Trek wash- boldly go where no potter has gone before. Nerd Link to comment Share on other sites More sharing options...
PeterH Posted January 13, 2016 Report Share Posted January 13, 2016 This may be of mild interest and encouragement. https://in.pinterest.com/pin/535787686896923768/ ... and this mentions another wash, and touches on the H&S of lithium. http://www.potters.org/subject66845.htm Also keep in mind those in the population already prescribed lithium! Link to comment Share on other sites More sharing options...
Matt Oz Posted January 13, 2016 Report Share Posted January 13, 2016 Fun fact, the original 7UP had a small amount of lithium in it. Link to comment Share on other sites More sharing options...
Babs Posted January 13, 2016 Author Report Share Posted January 13, 2016 yeh, see, someone's done it! Thanks for the links Peter, no need for prescriptions, just breath.......in my shed during glaze mixing. Not to be practiced at home.. Underneath a glaze may give some life?? Link to comment Share on other sites More sharing options...
neilestrick Posted January 13, 2016 Report Share Posted January 13, 2016 Spodumene can be used to make a toasty clay body, but it's not that simple. It will dramatically reduce the shrinkage rate of the clay, and make glaze fit a real problem. A.R.T. Clay used to make a body called Orangestone, a beautiful toasty orange color. Lots of spodumene. The shrinkage rate was around 6%. Most glazes wouldn't fit it- many would shiver or do other weird things. Most people just used it raw for sculpture or jewelry. Flameware bodies are often high in lithium because it reduces the expansion rate. I've heard of flameware bodies with 0% shrinkage, or even expansion. Link to comment Share on other sites More sharing options...
rayaldridge Posted January 13, 2016 Report Share Posted January 13, 2016 As Neil says, spodumene has been used to develop flameware bodies, and from talking to potters who went that direction, glazing was a problem. Another reason why a spodumene wash would not be quite the same as a soda wash in terms of application is that soda will dissolve in water (and penetrate the clay body) but spodumene will not. I would echo the suggestion to try a slip with a little spodumene, if you want to see how it affects the surface. Link to comment Share on other sites More sharing options...
Babs Posted January 13, 2016 Author Report Share Posted January 13, 2016 Thanks Neil and Ray. I will try it on the unglazed bottom third of some bowls to see the effect, I'll overlap the glaze a little at the meeting point to see what happens. The insolubility of the Lithium would be why the recipe in one of the links above calls for bentonite to help with the suspension Link to comment Share on other sites More sharing options...
Babs Posted January 13, 2016 Author Report Share Posted January 13, 2016 Not using the slip , Neil with the non shrinkage info has scared me off, the slip may just drop off the pot right?? The amount required for a colour change is said to be quite a large percentage so I'm going to go with the wash applied just before glazing. Link to comment Share on other sites More sharing options...
rayaldridge Posted January 13, 2016 Report Share Posted January 13, 2016 Babs, if I were experimenting I think I'd try a very thin slip on a test tile to see what happens-- maybe equal parts ball clay and spodumene as a starting point. If it pops off, you'll know immediately that it won't work, and waste no time with it. Or I might try a combo of Alberta slip and spodumene. My favorite high iron glaze in oxidation uses lithium to push it toward the red side of the spectrum. I really like slip, because it allows you all sorts of surface effects that are difficult to achieve otherwise. As an example, for many years I used a simple white slip on porcelain. The slip contained a high level of titanium. I used resists and carving to expose the raw porcelain underneath. Over this I used glazes that tended to develop microcrystalline surfaces if cooled very slowly. The effect was clear limpid color over the raw porcelain, and frosty crystalline surfaces over the slip, when fired at a normal cooling rate. Whatever you decide, let us know how it works out. Link to comment Share on other sites More sharing options...
neilestrick Posted January 13, 2016 Report Share Posted January 13, 2016 Babs, if I were experimenting I think I'd try a very thin slip on a test tile to see what happens-- maybe equal parts ball clay and spodumene as a starting point. I just read a report from someone yesterday that said he tried equal parts like that, and the test piece expanded 2 inches and stuck to the wall of his kiln. Even at cone 10 the clay wasn't hard- said it felt like cone 10 bisque. As a very thin, watery slip it could be interesting. Link to comment Share on other sites More sharing options...
rayaldridge Posted January 13, 2016 Report Share Posted January 13, 2016 Yeah, I think it would have to be very thin to have a decent chance of working. Maybe add some flux if it's too chalky a surface. Of course, at some point you have a hard engobe or maybe even a glaze, if you continue down that path. Link to comment Share on other sites More sharing options...
Babs Posted January 13, 2016 Author Report Share Posted January 13, 2016 Neil are you really trying to scare the beegeeebeees out of me? 2" HAve to be using it as a clay body ,right?? I'll try the thin slip on leather hard and also the wash, like the idea of slip as a textural thingie. Link to comment Share on other sites More sharing options...
rayaldridge Posted January 14, 2016 Report Share Posted January 14, 2016 Not to speak for Neil, but I'm sure he was referring to a clay body. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted January 14, 2016 Report Share Posted January 14, 2016 This thread reminded me of a very strange currie tile I had that was with spodumene. Adding clay actually seems to help the problem but silica makes it worse. Link to comment Share on other sites More sharing options...
PeterH Posted January 14, 2016 Report Share Posted January 14, 2016 Passed on in case you have bubble-trouble with a high-spodumene glaze. https://digitalfire.com/4sight/material/spodumene_1287.html Some types of spodumene do contribute to the formation of bubbles in the glaze slurry. You can wash spodumene before use to alleviate this issue (mix it well in plenty of hot water, allow to settle overnight, pour off the water the next day and dry it). Link to comment Share on other sites More sharing options...
Babs Posted January 15, 2016 Author Report Share Posted January 15, 2016 Rereading this, I realised that most of you swung straight on to using Lithium Carbonate. Is this because it is less refractory that the spodumene, or why? Link to comment Share on other sites More sharing options...
earthfan Posted January 28, 2016 Report Share Posted January 28, 2016 The spodumene supplied by the Greenbushes mine is a fine sand that is 88% spodumene and 12%silica. I fired a little bowl of it to about cone 7 and it converted to beta spodumene, puffed up and turned into a fine pink powder. It did not melt at that heat and didn't even fuse to the bowl it was in. Spodumene has one molecule of lithium oxide to one molecule of alumina to 4 of silica, so it is like feldspar, but with a lower proportion of silica. Spodumene has a negative co-efficient of linear expansion. It doesn't shrink when fired, it gets bigger. Lithium carbonate is Li2CO3 and is slightly soluble. That is what you need to spray on the raw clay to get a sheen. "Ceramics Monthly" of February 2015 has an article on spodumene. Link to comment Share on other sites More sharing options...
Babs Posted January 29, 2016 Author Report Share Posted January 29, 2016 Here are some small pots thrown for tests. I. soaked the spod, and there were bubbles as a poster mentioned. I then , non scientifically, as I am not really pursuing this other than interest arising from something I read. mixed it with the throwing slip from the pots. I applied this as they came off the hump. Some areas, thicker app. the spod clay mix was quite glossy. Link to comment Share on other sites More sharing options...
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