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Usually describes a bamboo colored matte glaze (especially in reduction stoneware). These are normally achieved in a magnesia white matte by adding a small amount of iron (0.5-1%) and possibly some tin oxide opacifier.
A tin oxide addition can improve the visual of a cone 10R bamboo
This is the G2571A base dolomite matte recipe. The specimen on the left adds 4% tin and 1% iron oxide. The one on the right has 4% tin oxide and 0.5% iron oxide.
Reduction glaze gone astray returns color on an oxidation refire
Refired to 1950F. The recipe is very flux heavy (high feldspar) dolomite:spodumene matte, zero silica, 4% tin oxide and less than 1% iron oxide. Sounds like crystallization territory. The plate on the left is the way it normally fired. On the right that way it started firing. The mug on the bottom has been refired at 1950F in oxidation and the color is back. The tin is likely a catalyst for the crystallization that occurred in the original result. Could be a fragile mechanism. Anyway, a period of oxidation at the end of the reduction firing should solve this.
Out Bound Links
G2571A - Cone 10 Silky Dolomite Matte Base Glaze
A cone 10R dolomite matte having a pleasant silky surface, it does not cutlery mark, stain or craze on common bodies
2003-12-18 - A standard Plainsman Clays cone 10R dolomite matte glaze used for many years. It came from another recipe that employed calcium carbonate to supply th...
Dolomite matte glazes are normally fired at cone 10 and often have a very pleasant-to-the-touch silky-feeling surface. This unique feel is a product of tiny discontinuities in the glaze melt (phase changes) that exhibit at the surface as tiny waves and ripples. This phenomenon is thought to be assoc...
GR10-J1 - Ravenscrag Cone 10R Bamboo Matte
Plainsman Cone 10R Ravenscrag Slip based glaze. It can be found among others at http://ravenscrag.com.
2013-07-23 - This is GR10-J dolomite matte (a Ravenscrag version of G2571A) with 1% iron oxide added (to produce a bamboo effect).
An alternative bamboo (for bo...
By Tony Hansen