SRB09
Cone 09 · Bends 955°C (1751°F) at 300°C/hr, measured in a gas-fired kiln · 28.6 mm (1⅛ in) tall, ceramic · Sized for the Dawson Kiln-Sitter shut-off device · Tapered — placement under the sensing rod is worth about half a cone · Deforms 7 to 10°C (12 to 18°F) earlier than a self-supporting cone · Chart values assume a 23.8 mm (15/16 in) mounting height · Red iron-bearing — no Iron Free cone is published in this size · Contains crystalline silica — do not grind or breathe the dust
$0
Bends at 955°C (1751°F) at 300°C/hr. Sized for the Dawson Kiln-Sitter, where the sensing rod presses it to about a 90° bend and cuts the power. For craft and art bodies, wall tile and glazes.
Cone 09 in Orton's small regular (SRB) series, sized for the Dawson Kiln-Sitter rather than the kiln shelf. It bends at 955°C (1751°F) at 300°C/hr, the only rate Orton publishes for this size, measured in a gas-fired kiln. The taper matters: the thin end under the sensing rod fires cooler, the thick end hotter, worth about half a cone either way. Small cones deform 7 to 10°C (12 to 18°F) earlier than a self-supporting cone, so never substitute a self-supporting figure for one of these. Cones 010 through 3 are the red iron-bearing compositions and can fire matte, green or bloated without oxygen, and Orton publishes no Iron Free cone in this size.
