falconium Posted June 9, 2008 Share Posted June 9, 2008 I have received already baked terra cotta tile. My reading on the subject indicates the red color comes from oxidized iron in the soil. Any suggestions on a solution that would turn the red tile to yellowish-white after it has been manufactured? Out of thousand tiles we get 100 or so that are like this naturally, but no one knows how to control it. I've been told excess heat during firing can bake out the color, also iron deficient soils. But what about after it is made? Any ideas? Link to comment Share on other sites More sharing options...
hermanntrude Posted June 9, 2008 Share Posted June 9, 2008 paint it, or use a dye. perhaps a reducing agent? Link to comment Share on other sites More sharing options...
bored_teen Posted June 12, 2008 Share Posted June 12, 2008 maybe have a powerful electromagnet remove the oxidized particles during baking? Link to comment Share on other sites More sharing options...
hermanntrude Posted June 13, 2008 Share Posted June 13, 2008 perhaps if it's excess heat that does it, you could apply heat to certain areas using something like a branding iron? it might crack the substrate though, uneven heating... moved to inorganic chemistry Link to comment Share on other sites More sharing options...
YT2095 Posted June 13, 2008 Share Posted June 13, 2008 I wonder if Oxalic Acid may help? it`s pretty good at removing Iron based coloring, although being Baked / Calcined, it may prove Much harder than that! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now