Specific gravity

Definition

Specific gravity is a dimensionless quantity that measures the ratio of the density of a substance to the density of a reference substance, usually water for liquids and solids. This value helps in identifying minerals because it provides insight into their composition and potential uses. Knowing specific gravity is essential in mineral classification as it aids in distinguishing between minerals with similar physical properties.

5 Must Know Facts For Your Next Test

1. Specific gravity is calculated using the formula: Specific Gravity = Density of Substance / Density of Water.
2. It is a crucial property for mineral identification because it can differentiate minerals that appear similar in color and crystal form.
3. Minerals with a higher specific gravity tend to feel heavier than those with lower specific gravity when held in hand.
4. Specific gravity values can vary significantly among minerals; for example, gold has a high specific gravity of around 19.3, while quartz has a much lower value of about 2.65.
5. In practical terms, specific gravity can help geologists determine whether certain minerals might be economically viable to extract based on their density and the ease of separation from surrounding materials.

Review Questions

• How does specific gravity contribute to the process of mineral identification?
  • Specific gravity plays an important role in mineral identification as it helps distinguish between minerals that may look similar but have different densities. By measuring the specific gravity, geologists can gain insights into the composition and potential uses of the mineral. Since different minerals have characteristic specific gravity values, this property serves as an additional tool alongside other physical properties like color and hardness in accurately identifying minerals.
• Discuss how specific gravity can affect the economic viability of mineral extraction processes.
  • Specific gravity directly impacts the economic viability of mineral extraction by influencing how easily minerals can be separated from one another during processing. Minerals with higher specific gravities may require less energy and fewer resources to concentrate and extract since they tend to settle more rapidly during separation techniques like floatation. Thus, understanding the specific gravities of target minerals enables geologists and mining engineers to develop more efficient extraction methods, ultimately affecting profitability.
• Evaluate the implications of using specific gravity as a mineral classification tool in relation to environmental sustainability.
  • Using specific gravity as a classification tool has implications for environmental sustainability as it can lead to more efficient mineral exploration and extraction practices. By accurately identifying and classifying minerals based on their specific gravities, mining operations can minimize waste and reduce environmental impacts associated with inefficient extraction methods. This precision allows for targeted resource management, which is crucial in preserving ecosystems and reducing the footprint of mining activities on the environment.

Related terms

density: Density is the mass per unit volume of a substance, often expressed in grams per cubic centimeter (g/cm³).

mineral: A mineral is a naturally occurring inorganic solid with a specific chemical composition and a crystalline structure.

floatation: Floatation is a method used to separate minerals based on differences in their specific gravities, allowing for the concentration of valuable materials.