How does fluorescence influence a diamond's value?

Fluorescence in diamonds refers to the phenomenon where a diamond emits a visible light, typically blue, when exposed to ultraviolet (UV) light. The impact of fluorescence on a diamond's value can vary depending on several factors, which is why the correct answer indicates that it can enhance or detract from the value.

In certain situations, fluorescence can enhance the appearance of a diamond, especially in higher color grades (such as D to H), where the blue fluorescence can make the diamond appear whiter or mask any slight tints. This can make these diamonds more appealing to some buyers, potentially increasing their value.

Conversely, in diamonds with lower color grades (like I and below), strong fluorescence may cause the diamond to appear oily or cloudy, which could detract from its value. Therefore, the overall effect of fluorescence is nuanced, as it can contribute positively in some cases while negatively impacting value in others.

Other options provided do not reflect this complexity. For instance, stating that it always increases value overlooks the variability in buyer perception and the specific characteristics of the diamond. Similarly, claiming it has no effect disregards the documented reactions in the market. Lastly, limiting its significance to daylight is misleading, as fluorescence can be examined under UV light sources