Colour appearance has been extensively studied. It was found that assessing the third dimension of colour appearance, such as chroma, colourfulness or saturation attributes, normally are more inconsistent than for other two dimensions (lightness and hue), even with experienced observers. Two psychophysical experiments were conducted to address the issue using British and Korean observers respectively. The following word scales to represent the third dimension were scaled by observers: ‘bright’, ‘light-heavy’, ‘active-passive’, ‘fresh-stale’, ‘clean-dirty’, ‘clear’, ‘boring’, ‘intense-weak’, ‘saturated’, ‘vivid-dull’, ‘distinct-indistinct’, ‘full-thin’, and ‘striking’. All observers did not have any colour science background, nor did they receive any training about each word scale. Predictive models of saturation and of vividness were developed to fit the experimental results. They reflect novice observers' view of colour appearance.