How Are Mugs Made?

Mugs are a staple in almost every kitchen — perfect for sipping coffee, tea, or hot chocolate. But have you ever wondered how these handy vessels are made? The process combines art, science, and a touch of tradition. Whether it's a plain white mug or a colorful, custom-designed cup, the journey from raw material to your cupboard is fascinating. Here's a closer look at how mugs are made.

1. Material Matters: Starting with Clay

Most mugs are made from ceramic, which starts as a mixture of clay, water, and other natural materials like feldspar and quartz. This blend is called "slip" when it's in a liquid state. Manufacturers may use porcelain or stoneware clay, depending on the desired finish and strength of the mug. Porcelain tends to be smoother and more refined, while stoneware is thicker and sturdier.

2. Shaping the Mug

There are several ways to shape a mug, but two of the most common are slip casting and wheel throwing.

• Slip Casting: Liquid clay is poured into plaster molds. The plaster absorbs water from the slip, causing a solid layer to form on the inside walls of the mold. Once it reaches the desired thickness, the excess slip is poured out, and the mold is left to dry. After drying, the mold is removed, revealing a clay mug.

• Wheel Throwing: This method is more traditional and often used by artisans. A lump of clay is placed on a potter’s wheel and shaped by hand. It takes skill and practice to form a uniform mug this way, making each one slightly unique.

3. Drying and Trimming

Once the mug has its shape, it needs to dry to a leather-hard state — firm but still workable. At this stage, the handle is usually attached if it wasn’t formed in the mold. Artists or workers then trim and smooth the mug, removing rough edges and perfecting the shape. Logos or decorations can also be stamped or carved into the surface.

4. Bisque Firing

The dried mugs are then loaded into a kiln and fired at a lower temperature in a process called bisque firing. This hardens the clay and prepares it for glazing. After this step, the mugs are durable but still porous and pale in color.

5. Glazing

Glaze is a liquid mixture of minerals that forms a glass-like surface when fired. It adds color, shine, and a protective coating to the mug. Mugs can be dipped, sprayed, or brushed with glaze, and artists often use creative techniques to produce unique finishes.

6. Final Firing

The glazed mugs go back into the kiln for a glaze firing, usually at a higher temperature. This second firing melts the glaze and fuses it to the mug, creating the smooth, often glossy finish we’re familiar with. After cooling, the mugs are ready to be packed and used.