Graphite Crucible
Excellent quality crucibles are resistant to high heat and thermal shock. Natural flake graphite and silicon carbide bonded with fire clay.
Spout for easy pouring. Dimensions and capacities may vary slightly from those listed below.
| Style Number | Diameter x Height | 18K Gold Capacity (dwt/grams) | |
|---|---|---|---|
| 4/0 | 2-3/8" x 3" | 600 / 935 | |
| 1 | 3-1/8" x 3-5/8" | 1500 / 2330 | |
| 2 | 3-11/16" x 4-1/2" | 2400 / 3730 | |
| 3 | 4-1/8" x 5-5/8" | 4320 / 6720 | |
| 4 | 4-9/16" x 5-3/4" | 5120 / 7960 | |
| 5 | 5" x 6-1/4" | 6800/10,575 | |
| 6 | 5-1/4" x 6-1/2" | 7830 / 12,175 | |
| 8 | 6" x 7-1/4" | 8841 / 13,750 | |
| 10 | 6-1/8" x 8-1/16" | 11574 / 18,000 | |
| 12 | 6-3/4 x 8-3/4 | 11574 / 18,000 |
To season a graphite crucible, you can heat it and coat it with borax:
1. Heat the crucible
Heat the crucible until it's red hot, which can take 20–40 minutes. You can heat it in an oven at 300°F for an hour, or in a furnace.
2. Apply borax
Sprinkle borax into the crucible while it's hot. Borax is a cleaning chemical that helps insulate metal, lubricate it, and protect the crucible.
3. Let it cool
Allow the crucible to cool slowly. Don't spray it with water, as it could explode.
You should also preheat a new or completely cooled crucible before using it for melting or holding operations.
