The red ruby, often referred to as the "king of gemstones," is known for its vibrant red color, which can range from pinkish to blood-red. Its color is primarily due to the presence of chromium. Rubies are a variety of corundum, and they are one of the hardest gemstones, scoring 9 on the Mohs scale of mineral hardness.

In terms of metaphysical meanings, rubies are believed to symbolize passion, love, and courage. They are thought to enhance energy, promote motivation, and inspire a sense of confidence. Additionally, rubies are often associated with the root chakra, which is linked to feelings of safety and grounding.

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