LRB09
Cone 09 · Bends 917°C (1683°F) at 60°C/hr (medium) · Bends 928°C (1702°F) at 150°C/hr (fast) · 63.5 mm (2½ in) tall, ceramic · Mounts in a cone plaque, clay pat or wire holder — 51 mm (2 in) exposed at 8° · Endpoint is a 90° bend · Red iron-bearing — use the Iron Free series for reduction · Contains crystalline silica — do not grind or breathe the dust
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Bends at 917°C (1683°F) at 60°C/hr, or 928°C (1702°F) at 150°C/hr. For craft and art bodies, wall tile and glazes. Mounts in a cone plaque, clay pat or wire holder.
Cone 09 in Orton's large regular (LRB) series, for use on the kiln shelf. It bends at 917°C (1683°F) when the last 100°C of the firing is held at 60°C/hr, and at 928°C (1702°F) at 150°C/hr. The rate matters because a cone measures heat-work, the combined effect of time and temperature, not temperature alone. Orton lists this part of the range for craft and art bodies, wall tile, glazes and some structural clay. Cones 010 through 3 are the red iron-bearing compositions and can fire matte, green or bloated without oxygen; Orton recommends the Iron Free series for reduction.
