Look at the finish inside a mug
Look inside the mug as closely as you look at its decoration. A finish needs to suit drinking, cleaning and the care instructions supplied with it.
Look past the outside colour
A mug can have a rough, textured exterior and a smooth glazed interior. That combination may be deliberate. What matters is understanding which surfaces are intended to meet the drink and how the maker says to care for them. Do not assume that every ceramic object shaped like a cup is suitable for food use; decorative pottery should be identified as such before it joins the kitchen cupboard.
Inspect a new mug in good light, especially the bottom inside and the area below the rim. Look for damage, sharp roughness or cracks rather than trying to judge a glaze recipe by eye. A decorative pattern can include speckles or colour variation without being defective. If something seems uncertain, send the seller a clear photograph and ask about that specific feature before using the mug.
Appearance does not establish performance
Shiny and matte finishes can both be used on functional pottery, depending on how they are made. A glossy surface is not a universal guarantee of stain resistance, and a matte one is not automatically unsuitable. The manufacturer's information is more useful than a general rule based on shine. Check the listed dishwasher and microwave suitability for the exact product, including any metallic decoration or special finish.
Do not treat the unglazed foot underneath a mug as proof that the interior is unsealed. The base may be left unglazed as part of the firing process, while the drinking surfaces are finished differently. Check that the foot feels suitable for the table or use a clean coaster. Grit caught under even a smooth base can mark a surface when the cup is pushed around.
Keep cleaning proportionate
Use the maker's cleaning guidance and start with ordinary gentle washing. Aggressive abrasives can change a surface, and a household remedy recommended for one ceramic product may not suit another. A dark mark might be deposited material rather than a deep scratch, but it is unwise to diagnose every line from its colour alone. Ask the manufacturer if a new mug develops an unfamiliar mark quickly.
When shopping online, photographs of both the interior and the base help you understand the finish. Product descriptions should make clear that the item is drinkware and state any relevant use restrictions. Avoid a listing that relies entirely on the words handmade or artisan while giving no functional information. An attractive glaze is part of the appeal of a mug, but the everyday value comes from a sound drinking surface, clear care instructions and a finish you can maintain without guessing.
Further information