Left is Plainsman M340. Right is M390. Each mug has been white engobed inside and half-way down the outside. The insides have been glazed using G2926B clear. The inside surface has more depth and has a richer appearance than you could achieve using a white glaze (especially over the dark burning body). The outside of the left one is Alberta Slip base GA6A using Frit 3195 (it produces a more stable glass of lower thermal expansion). The outside glaze on the right is the clear plus 4% iron oxide. This technique of using the engobe enables porcelain-like functional surfaces on the insides and striking visual contrast and character on the outside of the dark body mug.
Pages that reference this post in the Digitalfire Reference Database:
GA6-A - Alberta Slip Cone 6 Amber Base Glaze, L3954B - White Cone 6 Engobe for Plainsman M390, M340, How to Liner-Glaze a Mug, GA6A Alberta Slip base using Frit 3249 and 3195 on buff body, Four drops of Davan deflocculant fixed the problem!, Rich, natural but vibrant colors. How was this cone 6 mug made?, Engobe
This post is one of thousands found in the Digitalfire Reference Database. Most are part of a timeline maintained by Tony Hansen. You can search that timeline on the home page of digitalfire.com.