How is a specific quality range of rough gemstones determined?

The specific quality range of rough gemstones is primarily determined by several key factors, including color, size, clarity, and price. Color impacts a gemstone's desirability, as different shades can significantly alter the value of a stone; for example, a deep, vibrant blue sapphire is usually more sought after than a lighter hue. Size also plays a crucial role, as larger gemstones can command a higher price. Clarity relates to the presence of inclusions or blemishes, which can affect the stone's beauty and value—higher clarity typically means a more valuable gem.

Price is a composite measure influenced by all these factors, along with market conditions and demand for specific types of gems. Thus, by analyzing these attributes collectively, gemologists can assess the overall quality range of rough stones, enabling proper classification and valuation in the market. Other options refer to important aspects like origin and treatment history, yet they do not encompass the complete picture of how quality is assessed in a gemstone. Carat weight is also essential but is not the only determinant of quality, since the factors mentioned above often play a more significant role in valuation.