Which Two Gems Are Special Versions of the Common Mineral

question 42

Multiple Choice

Which two gems are special versions of the common mineral corundum (Al₂O₃) ?

• A)emeralds and rubies
• B)emeralds and sapphires
• C)aquamarines and emeralds
• D)sapphires and rubies

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Definitions:

[H+]

Denotes the concentration of hydrogen ions in a solution, commonly associated with the acidity of a solution.

[H+]

Symbol denoting the concentration of hydrogen ions in a solution, indicative of its acidity.

HCl

Hydrochloric acid, a strong acid consisting of hydrogen and chlorine that is often used in industrial and laboratory settings.

K

The chemical symbol for potassium, a soft, silvery-white metal that is highly reactive with water.