Skip to product information
1 of 5

Flag of San Francisco - Color Changing Mug 11oz

Flag of San Francisco - Color Changing Mug 11oz

100 in stock

Regular price $17.99 USD
Regular price Sale price $17.99 USD
Sale Sold out
Shipping calculated at checkout.

Flag of San Francisco - Color Morphing Mug Design

This is the official flag of San Francisco, California, built around a rising phoenix and a Spanish motto set in blue, gold and white.

Visual Elements & Composition

The phoenix is the centrepiece, rising in gold and commanding the field. Blue, gold and white make up the palette, with blue carrying the sky, gold given the most visual weight, and white providing the clean ground that keeps the composition sharp. The Spanish motto, "Oro en Paz, Fierro en Guerra," appears as lettering within the design, so text and image share the same space and read as one civic emblem.

Meaning & Symbolism

The phoenix stands for the city's resilience and rebirth after the multiple disastrous fires of the 19th century. Each colour carries its own meaning: blue for the city's skies, gold for commerce and industry, and white for pure purpose. The motto translates as "Gold in Peace, Iron in War," pointing to San Francisco's commercial prosperity and its role as a military embarkation point during the Spanish-American War. The design was originally created around 1900 and officially adopted on December 16, 1940, making it a historical tribute to the Bay Area.

Reading the Design on a Mug

A mug is turned in the hand, so the flag rotates past the eye as you drink, and the phoenix is never seen all at once. The heat-reactive surface holds the artwork back until a hot drink is poured in, then brings it up through the cup. The emblem's story of rising from fire suits that effect exactly, since the design only fully appears once heat is added.

Size

Bulk Discounts Available

These discounts apply to all products.

Buy 2
10% OFF
Buy 3+
20% OFF
Buy 5+
30% OFF
Buy 10+
40% OFF

Automatically applied at checkout.

View full details

Color-changing ceramic mugs with a glossy finish, black exterior, and white interior. Available in one size: 11 oz (≈330 ml). Heat-reactive coating reveals your custom design when filled with hot liquid. BPA- and lead-free, with a comfortable C-handle.

This mug brings a playful twist to the daily coffee or tea ritual. At room temperature, it looks like a simple black mug with a glossy finish. But add a hot beverage, and your chosen design fades into view, showing vivid colors against the white interior.

The ceramic body is durable enough for repeated use, while the C-shaped handle balances comfort and grip. Printing uses sublimation techniques that fuse color into the heat-reactive surface for crisp results when the design appears.

  • Material: ceramic with glossy black exterior and white interior.
  • Size: one standard size, 11 oz (≈330 ml).
  • Finish: glossy glaze with heat-sensitive surface.
  • Printing: sublimation process produces crisp, vibrant colors.
  • Safety: BPA-free and lead-free, suitable for everyday drinks.
  • Effect: design is faintly visible when cold, fully revealed when hot.

Perfect as a novelty gift or a fun personal mug, the heat-reactive design makes coffee breaks more engaging. It works well for morning coffee, afternoon tea, or hot chocolate.

  1. Daily routine: fill with any hot beverage to reveal your chosen artwork.
  2. Gifting: the “magic” reveal makes it a memorable present for birthdays, holidays, or office exchanges.
  3. Office use: sparks conversation while still being practical for everyday drinks.

Note: for best results, avoid designs that rely heavily on deep black backgrounds, as they may blend with the mug’s surface when cold.

Unlike standard mugs, color-changing mugs require gentler care to preserve the heat-reactive coating. Hand-wash only — avoid the dishwasher and abrasive scrubbers, which can damage the finish and reduce the effect.

The mug is safe for short microwave use when heating liquids, but repeated high-heat cycles may shorten the lifespan of the coating. Always allow the mug to cool before washing.

Available in one classic size: 11 oz (approximately 330 ml). It’s large enough for most standard coffee makers and fits comfortably in most cabinets.

Size guide

All measurements are product dimensions in inches.

11 oz
Height (in) 3.78
Diameter (in) 3.23
Diameter w/ handle (in) 4.76

Note: measurements are approximate; slight variations may occur due to manufacturing tolerances.