MariaHowardCeramics

Hi there, I wonder if anyone can help explain why one of my go-to glazes is acting completely differently to past results. I am using stoneware. The glaze is Turner's white with 5% black iron oxide added and mixed in. In the past this has created a lovely deep brown which I have used everywhere. However I made a new batch up last week and fired it (slow glaze, cone 6 on an L&L kiln) and it came out a colour that looks like buttercream. At first I thought it might be because I added a soak to the firing to make sure the bottom layer got fully glazed but I did another firing this week with no soak and the same thing happened, albeit with a smoother, nicer effect than the first time. I am going to buy some cones to check the temp for sure but it's still very weird... I am also using a clay that looks more pink than buff when bisqued – could this have an effect? Thanks! Maria