oldlady Posted April 28, 2016 Report Share Posted April 28, 2016 this is the edge of my glaze bucket which contains Nutmeg, a glaze recipe i messed up but was fixed by John Hesselberth several years ago. the bucket was sitting around waiting for me to use it and this is what i found when i opened it after 6 months. the darker stuff at the edge is crystalline and very stiff. it is hard to scrape off if it sits too long. i will list the ingredients, please tell me what caused this effect. it has happened with other recipes over the years and i have never discovered what causes this. i does not happen to every glaze. ingredients are dolomite, spodumene, ball clay (om4), silica, frit 3134, red iron oxide, yellow ochre, tin oxide and bentonite. the ingredient John used to fix my mistake was ball clay. Link to comment Share on other sites More sharing options...
neilestrick Posted April 28, 2016 Report Share Posted April 28, 2016 If you're getting crystals, it could be epsom salts precipitating out, if you used any to keep the glaze suspended. And could also be some soluble material coming out of the frit or spodumene. Link to comment Share on other sites More sharing options...
glazenerd Posted April 29, 2016 Report Share Posted April 29, 2016 After going through your list: spodumene would be on the top of my list of reactants. Had to look up to make sure: but naturally occurring lithium will decompose just like its man made cousin- lithium carb. These reactions occur at room temperature, releasing hydrogen gas. Two indicators I see: the top of the bucket is turning very dark- lithium turns black as it decomposes. Second- (if I am seeing the pic right) the upper left hand of the bucket looks like blisters have formed. Possible sign of hydrogen being released under the hardened glaze. Spodumene has 7% lithium, so it is a prime suspect. Iron oxide could react, but highly unlikely. The rest of the ingredients are basically inert at room temps. By chance do the other glazes that show this problem have some lithium source present? Nerd Lithium reacts with water easily, but with noticeably less energy than other alkali metals. The reaction forms hydrogen gas and lithium hydroxide in aqueous solution Link to comment Share on other sites More sharing options...
neilestrick Posted April 29, 2016 Report Share Posted April 29, 2016 I get a lot of hard flakes lining the buckets of my glazes that have 3134. Link to comment Share on other sites More sharing options...
oldlady Posted April 29, 2016 Author Report Share Posted April 29, 2016 knew you guys would have some ideas. it is cold out there today and i am not going to look for any other buckets with the problem tonight. it has been really cold, 49 degrees after a week of high 70s and i am sniffling and bundled up in lots of wool sitting next to a radiator. maybe tomorrow. Link to comment Share on other sites More sharing options...
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