This product has fine thermal conductivity and thermostability. When used in hyperthermal condition, it has certain resistance to snap hyperthermal and cold for it has small thermal expansivity. And it has chemical stability that has nice resistance to strong acid and strong base. With those properties, it is very suitable to melt various gold, silver, copper, aluminum, zinc and other metals. Features: Fine thermal stability: aims at the using conditions of graphite crucible that snap hyperthermal and cold. Fine corrosion resistance and shock resistance: ensure the reliability of product quality. Fine resistance to strong acid and strong base. Fine thermal conductivity: shorten the melting time and save energy. The ash content is less than 0.1%, ensuring the metals is not contaminated in smelting. Suitable to melt various metals, like gold, silver, copper, aluminum, zinc and others. Chemical stability, long service life and attractive appearance. More practical than ordinary material and able to withstand high temperature. Specifications: Size: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 (optional) Specific size (External Diameter * Height): 20 * 20mm / 0.08 * 0.08in (size 1) 25 * 25mm / 0.98 * 0.98in (size 2) 30 * 40mm / 1.18 * 1.57in (size 3) 35 * 35mm / 1.38 * 1.38in (size 4) 40 * 40mm / 1.57 * 1.57in (size 5) 40 * 60mm / 1.57 * 2.36in (size 6) 40 * 80mm / 1.57 * 3.15in (size 7) 50 * 50mm / 1.97 * 1.97in (size 8) 50 * 80mm / 1.97 * 3.15in (size 9) 60 * 60mm / 2.36 * 2.36in (size 10) 75 * 75mm / 2.95 * 2.95in (size 11) Refractoriness: 1500 degrees C Carbon content: 99.9% Bulk density: 1.75g/cm3 Package size: 20 * 20 * 20mm / 0.08 * 0.08 * 0.08in (size 1) 25 * 25 * 25mm / 0.98 * 0.98 * 0.98in (size 2) 40 * 30 * 30mm / 1.57 * 1.18 * 1.18in (size 3) 35 * 35 * 35mm / 1.38 * 1.38 * 1.38in (size 4) 40 * 40 * 40mm / 1.57 * 1.57 * 1.57in (size 5) 60 * 40 * 40mm / 2.36 * 1.57 * 1.57in (size 6) 80 * 40 * 40mm / 3.15 * 1.57 * 1.57in (size 7) 50 * 50 * 50mm / 1.97 * 1.97 * 1.97in (size 8) 80 * 50 * 50mm / 3.15 * 1.97 * 1.97in (size 9) 60 * 60 * 60mm / 2.36 * 2.36 * 2.36in (size 10) 75 * 75 * 75mm / 2.95 * 2.95 * 2.95in (size 11) Package weight: 7g / 0.25ounce (size 1) 15g / 0.53ounce (size 2) 30g / 1.06ounce (size 3) 36g / 1.27ounce (size 4) 45g / 1.59ounce (size 5) 65g / 2.29ounce (size 6) 90g / 3.17ounce (size 7) 68g / 2.4ounce (size 8) 120g / 4.23ounce (size 9) 128g / 4.51ounce (size 10) 270g / 9.52ounce (size 11) ? Note: 1. Please store the product in dry place and do not get it wet. 2. Please avoids water after dry the product. 3. Be careful not to give a impact force on it. 4. Please allow a little difference due to manual measurement. Package List: 1 * Graphite Crucible