How to Test If the Ceramic Material Is Over Fired?
- 1). Tap the ceramic item with your finger. If the ceramic material makes a dull thud, it may be over fired.
- 2). Dip your finger into water and dab the wet finger on the ceramic object. If the ceramic soaks up the water quickly, within 3 to 5 seconds, it may be over fired.
- 3). Run your fingernail over a side of the ceramic object. If it flakes off or cracks, the ceramic is over fired.
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