Heat Sensitive Colour Changing Coffee Mug

This Mug from Velleora Home Decor is glazed with a heat-sensitive coating that goes from opaque to clear as hot liquid is poured in, revealing a hidden design that is invisible when the mug is cold.

The reveal is the whole gift. Handed over cold it looks like a plain mug; the design only appears once the recipient makes a drink, which makes it a considerably better novelty than a printed slogan they can read immediately.

Two designs are offered. The effect reverses as the drink cools, so it works every time rather than fading after a few uses. Hand wash only - a dishwasher will strip the thermal coating within a few cycles, which is the single most common way these mugs are ruined. Avoid abrasive scourers, do not microwave it, and expect the effect to soften gradually over years of use.

• Heat-activated colour changing glaze
• Design hidden until hot liquid is added
• Reverses as the drink cools
• Two design options
• Hand wash only - no dishwasher
• Do not microwave or scour