Observe the Appearance: A good porcelain cup should have a smooth and even appearance, free from cracks, bubbles, or uneven coloring. The glaze should be fine and smooth, without noticeable graininess or peeling.

Tap and Listen: Gently tap the body of the cup with your hand. A good porcelain cup will produce a clear and ringing sound, while an inferior cup will make a dull sound.

Feel the Weight: Generally speaking, a good porcelain cup will be relatively heavier, indicating that it is made with higher-quality materials and is more sturdy and durable.

Check the Brand and Reputation: Choosing porcelain cups from well-known brands or those with good reputations usually means they have undergone strict quality control and inspection.