Question

why might two people describe a minerals luster differently?
○ luster determination is subjective
○ luster depends on the time of day
○ luster changes over time
○ only experts can determine true luster

Explanation:

Luster is the way a mineral reflects light. Since it is often described using terms like "metallic", "vitreous" etc., perception can vary between individuals, making it subjective. Time - of - day doesn't directly affect a mineral's luster as it's an inherent property. While some minerals may weather and change luster over long periods, this isn't the main reason for different immediate descriptions. And it's not true that only experts can determine luster as it's a basic observable property.

Answer:

Luster determination is subjective