Apache’s micaceous clay. The recipe of that clay comes from the Apache descent, Felipe Ortega, placed in New Mexico, and it reproduce the old tradition of micaceous clay pottery over 400 years ago.
It is composed of red clays with a low thermal expansion coefficient, which provide high resistance to thermal shock (maximum resistance when fired at 950 ºC). In addition, it contains an abundant mica matrix that gives it elasticity and a highly distinctive, recognizable finish. Its original Apache character is achieved after wood firing. Available in extruded body (moist form).
Firing range*: 920-1000 ºC / Cone 08-06
Water content: 24 %
Plasticity (IP Atterberg): 23
Carbonate content (CaCO3): 0.0 %
Drying shrinkage: 4.5 %
Firing shrinkage 950 ºC: -0.3 %
Porosity (water absorption) at 950 ºC: 17.0 %
Dry bending strength: 5.4 N/mm2
Fired bending strength 950 ºC: 20.3 N/mm2
Thermal coefficient 950 ºC (25-500 ºC): 56.2x10^-7 ºC^-1
Recommendations for glaze use
Due to the low thermal expansion coefficient of the body, glazes may craze. It is recommended to use glazes with a low dilatometric coefficient or to mix the usual glaze with a dilatometric adjuster.